Green Roofs Feasibility Study and City Wide Implementation Plan

City of Waterloo

Green Roofs Feasibility StudyAnd City Wide Implementation Plan Final Report December 2004

Revised by City of Waterloo ndash June 2005

Green Roofs Feasibility Study - City of Waterloo

CITY OF WATERLOO GREEN ROOFS FEASIBILITY STUDY And City Wide Implementation Plan

TABLE OF CONTENTS

EXECUTIVE SUMMARY i

ACKNOWLEDGEMENTS vi

10 INTRODUCTION 4

11 GENERAL 4 12 STUDY OBJECTIVE 5

20 GREEN ROOF DEFINITION 5

30 FEASIBILITY APPROACH 7

POTENTIAL GREEN ROOF BENEFITS 7 Primary Benefits7 Secondary Benefits7

31 STORM WATER MANAGEMENT 7 311 Common methods of controlling the storm water effects of new development 8 312 Common methods of controlling the effects of existing development 9 313 Potential water quality improvements in City Watercourses10 314 Flooding11

32 AIR POLLUTION REDUCTION 12 33 ENERGY EFFICIENCY 13 34 URBAN HEAT ISLAND 15 35 GREEN SPACE 15 36 CONNECTIVITY TO AIRBORNE SPECIES (HABITAT) 16 37 EXTENSION OF ROOF LIFE SPAN 16 38 URBAN AGRICULTURE 17

40 CITY WIDE IMPLEMENTATION PLAN 17

41 CITY WIDE PROGRAM 19 42 PROGRAMS IN OTHER AREAS 20 43 COSTS AND BENEFITS 21 44 POTENTIAL PARTNERS 23

50 PUBLIC INVOLVEMENT 23

Public Outreach 23 Articles in the KW Record Waterloo Chronicle and University Gazette 24 Green Roof Display boards 24 Physical Model of a sample Demonstration Site 24 Conference Poster24 Green Roof Display at GRCA Water Forum24

60 GREEN ROOF COSTS 24

70 NEED FOR FURTHER STUDY AND RESEARCH 26

80 INCORPORATION INTO CITY PLANNING AND ENGINEERING POLICY 26

81 REGIONAL GROWTH MANAGEMENT 27


82 GREEN ROOF DESIGN GUIDELINES 28

90 DEMONSTRATION SITE SELECTION 29

91 INTRODUCTION 29 92 MUNICIPAL BUILDING SELECTION FOR GREEN ROOF APPLICATION 29

921 Municipal Building Inventory and Evaluation 29 992 Municipal Building Candidates 29 923 Building Categories- Municipal Building Selection Factors 30 924 Suitable Buildings for Green Roof Installation - Scoped Building Sites30 925 Evaluation Matrix 31

100 DEMONSTRATION SITE 31

101 VISIBILITY AND FUNCTION AS A DEMONSTRATION SITE 32 102 INITIAL SELECTED DEMONSTRATION SITE LOCATION 32 103 INITIAL DEMONSTRATION SITE DESIGN DEVELOPMENT 33

1031 Green Roof Design - Design Charette 33 1032 Green Roof Design Plan 33 1034 Technical Considerations33 1035 Social interest Considerations 34 1036 Access Considerations34

104 SAMPLE DEMONSTRATION SITE ASSESSMENT (WATERLOO PUBLIC LIBRARY) 35 1041 Condition of Existing Roof35 1042 Structural Assessment35 1043 Roof Drainage Plan 36

105 FUNCTIONAL FINAL DESIGN 36 1051 Xeroflor 36 1052 Physical Model of the Initial Demonstration Site37 1053 Xeroflor Extensive Roof System 38 1054 Performance Characteristics of the Xeroflor Green Roof38

1055 COST ESTIMATE 39 105 IMPLEMENTATION PLAN 39

110 CITY HALL GREEN ROOF 40

111 PLANNING 40 1111 Green Roof Design Plan 40 1112 Condition of Existing Roof41 1113 Structural Assessment41 1114 Roof Drainage Plan 41

112 IMPLEMENTATION COMPONENTS 42

120 RECOMMENDATIONS 45

Page 2


TABLES AND FIGURES On or after Page

Figure 11 Chain of Benefits helliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellip 5 Figure 34 Thermal Image helliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellip 15 Figure 40 City of Waterloo Building Assessment Templatehelliphelliphelliphelliphelliphelliphellip 17 Figure 401 Storm Water Management Areahelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellip 19 Figure 402 Energy Efficiency Maximization Areahelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellip 19 Figure 403 Urban Heat Island Areahelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellip 19 Figure 404 Air Pollution Potential Areahelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellip 19 Figure 405 Green Space Priority Areahelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellip 19 Figure 406 Overall Green Roof Benefit Maximization Areahelliphelliphelliphelliphelliphelliphellip 19

Table 401 City Wide Implementation Planhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellip 18

REFERENCES amp SOURCES A-E

APPENDICES

APPENDIX A ndash Steering Committee APPENDIX B ndash Public Outreach - Green Roofs Survey APPENDIX C - Workshop Proceedings APPENDIX D- Energy Efficiency Analysis APPENDIX E - Local Press Kitchener-Waterloo Record Waterloo Chronicle University Gazette

APPENDIX F ndash CRESTech Proceedings of Brainstorming Session APPENDIX G ndash Conference Poster APPENDIX H ndash City of Waterloo Municipally owned buildings APPENDIX I ndash Evaluation Matrix APPENDIX J ndash Xeroflor Technical Information APPENDIX K ndash Demonstration Site Sample Cost Estimate APPENDIX L ndash Examples of Green Roofs APPENDIX M ndashGreen Roof types APPENDIX N ndash Sample Implementation Plan

Page 3

Green Roofs Feasibility Study œ City of Waterloo

EXECUTIVE SUMMARY

The Federation of Canadian Municipalities granted the City of Waterloo $25000 to conduct a Green Roofs Feasibility Study and implement a Green Roof demonstration site on a City-owned building There are numerous types of Green Roof systems available and can be defined as a system of plants growing medium and rootwaterproof membranes that act as a whole to maximize the available environmental benefits on the roof of any type of new or old building The objective of this study is to determine which municipally owned buildings would be most suitable for a Green Roof and then select a suitable building to become a potential demonstration site

Green Roof technology offers many benefits especially for areas of high industrialization or dense population The City of Waterloo although not an area of high industrialization or dense population can still benefit from Green Roof technology Green Roofs can offer direct benefits in stormwater management mitigation of air pollution energy conservation heat island reduction increased opportunities for green space improve aesthetics and opportunities for urban agriculture horticultural therapy As a direct result of Green Roofs the Citylsquos creeks rivers and other water bodies would potentially experience environmental improvements Green Roof technology is also socially and economically beneficial due to the improved aesthetic value of the roof opportunity for horticultural therapy energy savings and extension of the underlying roof life

In order to facilitate the selection of a suitable demonstration site a steering committee comprised of City of Waterloo staff Region of Waterloo staff and local community and industry representatives was formed The steering committee participated in the various steps of the study which included

bull Public surveys community involvement bull Selection of city owned buildings which would be eligible for a green roof application bull Selection of a demonstration site bull Design of a demonstration site Green Roof bull Determining the feasibility of Green Roof technology in the City of Waterloo

Green Roofs Feasibility in the City of Waterloo

In order to determine if Green Roofs are feasible in the City of Waterloo a number of potential benefits were reviewed and evaluated based on whether or not Green Roofs could provide an environmental function or benefit A list of primary potential Green Roof benefits is provided below

bull Stormwater Management (SWM) ie water quantity quality and erosion control bull Air pollution reduction bull Energy conservation bull Reduction of mdashheat islandldquo bull Provision of Green Space (aesthetic and recreational benefits) bull Increased roof life (economic benefit) bull Connectivity to natural airborne species (environmental benefit) and bull Urban agriculture

Stormwater management is primarily responsible for attenuating increased runoff to levels that would have occurred prior to development Stormwater management focuses on water quality water quantity and erosion control Creek systems within the City of Waterloo have a potential to be improved in water quality specifically water temperature Green Roof systems can help to reduce elevated water

i


temperatures before discharging to creek systems and lakes The reduction in temperature reduces the occurrence of algae formation and promotes a healthier benthic community Creek health improvements have the potential to have far reaching rdquospin-offlsquo benefits that could work towards achieving a rdquobalancelsquo

In addition to improvements in water quality Green Roofs can also provide benefits in water quantity and erosion control Green Roof systems would decrease the amount of runoff flowing directly into creek systems and lakes which would in turn decrease the velocity and duration of the flow The reduced velocity and duration of the runoff will decrease the potential erosion to creek banks and creek beds The reduction in erosion will decrease sedimentation due to a decreased amount of suspended solids in the flow The overall result is improved creek stability and a reduction in the frequency of creek maintenance and rehabilitation

The Ontario Medical Association identified the population of Ontario as at risk for serious health problems due to the components of air pollution Publications such as Canadian Geographic have identified the City of Kitchener (the City of Waterloolsquos southern neighbor) as having air pollution issues It is noted that Ontario is not only dealing with air pollution generated from within province but also air pollution generated from the United States (to the south) It has been suggested that Green Roofs can remove 02kg of particulate matter from the air per year for every square metre of Green Roof Approximately 30 of phosphorous is airborne therefore Green Roofs could potentially reduce phosphorous as well

Increased energy efficiency from Green Roofs can be quantified in two ways increased insulation and heat gain reductions Increased insulation values can be obtained from the roof medium which increases the resistance for heat transfer through the roof system Additional layers of insulation can be added to further enhance the insulation value Reduced heat gain is achieved in part by the evapotranporative nature of the Green Roof plants and through the mechanical thermal break in the roof system Energy cost savings may be realized through the use of Green Roofs however the vertical walls of a building generally account for the majority of exposed surfaces thus the Green Roof energy saving potential is limited Therefore it is unlikely that the potential increase in energy efficiency could singly justify the implementation of Green Roofs systems

The rdquoHeat Islandlsquo effect can occur in urban centers Green Roofs can reduce the effect through the heat dispersion characteristics of Green Roof vegetation versus traditional roofing materials which typically absorb and emit heat This benefit would be most notable in warmer months allowing for more efficient cooling of buildings

Green spaces are generally required components of urban planning and a minimum area must be provided Green Roofs offer a unique potential for green space provisions in areas of high density or urbanization However by definition a green space must be visible by or exposed to the public This would be more effective in large urban areas where Green Roofs at low elevations can be visible from taller buildings The opportunities for this are few within the City of Waterloo due to a limited number high rise buildings as well as lower density urban development The value of green space benefits require further study as they relate to Green Roofs

Traditional rooftops offer no natural surface habitat for airborne species This is a significant concern in areas of increasing urbanization and density Green Roofs can provide shelter food and shade to many airborne species including birds and butterflies This can help balance the loss of natural habitat in urban areas and also provide connectivity to nature for urban residents

ii


Green roof systems are also economically beneficial Existing data has suggested that Green Roofs can extend the life expectancy of conventional roofing by a factor of 2 or 3 Essentially the increase in life expectancy can be attributed to the Green Rooflsquos ability to protect roof surfaces from solar radiation (ultraviolet) and harsh weather elements that impose material stresses The added protection decreases the degradation rate of the roof and increases the rooflsquos life expectancy Less frequent roof replacements would in turn reduce landfill waste

Urban agriculture could provide urbanites with an opportunity to grow fresh fruits and vegetables for their own consumption within an urban area However urban agriculture requires a specific roof loading in order to support the required amount of medium needed to grow food-producing vegetation There are not many opportunities to apply urban agriculture to existing buildings within the City of Waterloo (the rdquoParkadelsquo building in Uptown Waterloo is a potential candidate) but future buildings may be structurally designed to support the required loads

Public Involvement

The public was invited to provide their feedback by completing a questionnaire which was distributed as part of the Kitchener-Waterloo Metropolitan Area Survey 2003 The results of the questionnaire indicated that people are most concerned with air qualitypollution and water quality Recreation was ranked as the least important item A public workshop was held in partnership with the City of Waterloo Green Roofs for Healthy Cities the Region of Waterloo Ontario Power Generation and CMHC-SCHL The workshop provided an opportunity to learn about Green Roof technology Additional presentations and displays were presented at various locations and times Also articles were published in local newspapers describing the technology and the study

Selection and Evaluation of Initial Buildings

In order to determine which municipal building will be selected as the demonstration site for a Green Roof buildings had to meet a series of initial criteria The criteria is defined as follows

bull The demonstration site must be a City-owned building bull The demonstration site must be suitable for a flat roof installation bull The demonstration site must not be a heritage building bull The demonstration site must be in an area in need of the potential benefits Green Roofs can

provide bull The building should require roof replacement in the near future

The following buildings were initially selected as potential demonstration sites based on the criteria described above The list of buildings is as follows

1 City Hall œ 100 Regina Street South 2 Parkade œ Willis Way 3 Adult Recreation Centre œ Caroline Street 4 Library œ Albert Street 5 Waterloo Park Operations Building and Lions Lagoon

Selection of a Demonstration Site

The five buildings initially selected were further evaluated based on criteria developed to determine the optimum location for a demonstration site The criteria is described below

bull Function as a Demonstration Site bull Site LocationAccessibility

iii


bull Building Aesthetics bull Accessibility to Roof bull Visibility of the Site bull Access to the Site bull Suitability for Multiple Plots bull View From Rooftop bull Size of Roof

bull Structural bull Structural Retrofit Needs bull Ease of Roof Conversion

bull Cost bull Supply Access to Roof bull Ease of Maintenance bull Need for Roof Replacement

bull Performance bull Potential to Improve Energy Efficiency bull SWM Benefit Provided

Based on the evaluation criteria the Waterloo Public Library (Albert Street) was selected as the preferred demonstration site Through the installation of a rdquomini Green Rooflsquo on the City Hall entrance the Green Roof manufacturer Xeroflor based in Germany proposed a donation to the demonstration site whereby they would donate Green Roof materials to cover the roof

The Library Task Force is currently investigating opportunities and options for library operations the Albert Street building use as demonstration site was ultimately postponed until the task force recommendations have been approved by Council The Waterloo City Hall became the alternate choice for Green Roof implementation The Waterloo Public Library is recommended as the Green Roof demonstration site that could showcase both extensive and intensive green roof systems Xeroflor indicated that they would honour their proposed donation in the event that an alternative building could be used for Green Roof application

The design of the new Green Roof demonstration site should incorporate the components of the evaluation criteria and the results of the public survey The demonstration site should also incorporate social interests technical components and access components Technical components would follow the City of Waterloolsquos guidelines and practices pertaining to vegetative species while social components would include current and future library interests as well as provision of a learning and educational forum to showcase Green Roof technology Access components should focus on both physical access to the roof and visual access from inside and outside of the library

From a rdquocitywide perspectivelsquo the City of Waterloo was mapped and potential Green Roof benefit areas were delineated The delineated areas are described below

bull Stormwater Management œ Areas in need of SWM were determined based on age of storm system high imperviousness and insufficient space for traditional SWM and potentially poor water quality

bull Energy Efficiency œ Areas with a high concentration of older buildings are expected to have reduced energy efficiency

bull Urban Heat Island œ Areas with high imperviousness such as parking lots are expected to have high surface heat

iv


bull Pollution œ Areas with high traffic or industrialization are likely to have higher pollution levels

bull Green Space œ Areas where green space is scarce were expected to benefit from Green Roof implementation

Study Recommendations

The following recommendations resulting from the feasibility of Green Roofs as they relate to the City of Waterloo are as follows

bull Waterloo City Council should support and accept the Green Roof Feasibility Study bull The City of Waterloo should continue to investigate the possibility of implementing Green Roofs

on municipally owned buildings and ensure that the required resources can be accommodated bull The City of Waterloo should develop a policy regarding the use of Green Roofs in development

applications to encourage private use of Green Roof technology bull The City of Waterloo should continue to pursue partnerships and co-operative relationships with

related agencies corporations community groups and other jurisdictions to support the use of Green Roof technology

bull The Waterloo Public Library should consider a Green Roof system that includes the goals and objectives outlined in this report

v


ACKNOWLEDGEMENTS

The City of Waterloo would like to thank all of the members of the Steering Committee Members of Council and the individuals agencies and organizations for their input during the preparation of this study As well as for future work and potential partnerships to be formed related to the feasibility of Green Roofs in the City of Waterloo

Mr Wolfgang Behrens Xero Flor Germany amp Ms Joy Schmidt Xero Flor Canada Ltd Councilor Mark Whaley Ward 4 (Central) City of Waterloo Steven Peck Green Roofs for Healthy Cities Tim Ingold Manager New Homes Division Coldwell Banker Peter Benninger Reality Rebecca Shewfelt Student University of Waterloo Jim Brickman President and Founder The Brick Brewing Company Ltd Bradley Marsland Vice President Marsland Centre Stephen Murphy PhD Professor University of Waterloo Brad Bass PhD Adaptation amp Impacts Research Group Meteorological Service of Canada Environment Canada

Steering Committee Members

Peggy Bednarek City of Waterloo Jim Flanigan TSH Lynda Gale Waterloo Public Library Ryan Kennedy Region of Waterloo Elba Martell Region of Waterloo Cathy Matyas Waterloo Public Library Angela Mick TSH Kaaren Pearce Elevated Landscape Technologies Michael Pelton Enermodal Engineering Gregory Rose PhD Wilfred Laurier University Geri Quin City of Waterloo Sunda Siva City of Waterloo Nada Sutic University of Waterloo Ray Tufgar TSH John Turvey Bottomline Resource Group Jessi Ward City of Waterloo Wolfgang Wolter TSH

City Hall Green Roof Implementation Plan Team Alan McGregor Construction Management Jim Walsh City Hall Building Management Kevin Lobsigner City Hall Maintenance Karen Anderson Landscape Architect Bruce Hawkins Economic Development Bob Mavin Director Finance Tim Anderson Director Public Works Services Sunda Siva Team Leader Environmental Services Greg Romanick Director Recreation Services Paul Eichinger Director Economic Development John Miller Team Leader Supply amp Services

Special thanks to all the administrative assistancersquos interns technical staff family and friends who contributed to the Waterloo Green Roof Project

Sincerely

Karen Moyer Environmental Coordinator City of Waterloo

vi


10 Introduction

11 General

In 1985 the City of Waterloo was precedent setting in Ontario for initiating a framework for ecological planning and restoration This was initiated by adopting an lsquoEnvironment First Policyrsquo and followed up by carrying out a series of initiatives These included watershed and subwatershed planning to develop a management strategy for the City A number of measures and programs followed including planning and growth water resources air quality energy and resources environmental awareness and green space These strategic actions brought about environmental rehabilitation projects changes to municipal policies and a citywide monitoring strategy that is useful in providing guidance for the prioritisation of action in environmental health and protection endeavours for Waterloo In an effort to pursue technologies that sustain or enhance the environment given the strategies and goals in the Environmental Strategic Plan Green Roof technology presents itself as an opportunity worth investigating that can perpetuate this policy

The City of Waterloo received a grant of $25000 from the Federation of Canadian Municipalities (FCM) to develop a Green Roofs Feasibility Study and implement a Green Roof demonstration site on a City-owned building The Federation of Canadian Municipalities (FCM) has been the national voice of municipal government since 1901 FCM is dedicated to improving the quality of life in all communities by promoting strong effective and accountable municipal government Recently the Government of Canada endowed the Federation of Canadian Municipalities with $250 million to establish the Green Municipal Funds and support municipal government action to cut pollution reduce greenhouse gas emissions and improve quality of life In order to direct this feasibility study a steering committee comprised of City of Waterloo Regional Municipality of Waterloo local community and industry representation A description of the steering committee members is shown in Appendix A The steps required to develop this study involved a public outreach program to solicit public opinion on Green Roofs a Green Roof workshop a tour of City owned buildings development of an evaluation of the buildings to provide a preliminary selection of Green Roof candidates selection of a demonstration site and development of an implementation plan for the demonstration site as well as for use on a citywide basis These study components are explained in further detail in this report

Green Roof technology has existed for many years in Europe with Germany being one of the most aggressive developers of itrsquos use More recently densely populated cities in the US are using this technology namely Chicago and Portland Densely populated cities like Chicago benefit greatly from Green Roofs due to their urbanized nature Green Roofs are used in Chicago primarily for their ability to reduce the effects cause by the lsquoUrban Heat Islandrsquo to mitigate air pollution and for storm water management Canadian cities such as

Vancouver and Toronto have initiated some Green Roof usage but for primary objectives that can be distinct from other cities Toronto like Chicago benefit from Green Roofs in a similar way however the city of Vancouver comparatively a much less populated city has implemented Green Roof technology to protect their fisheries It can be noted thus that Green Roofs can offer different benefits to different cities depending on what the needs are and where they

Example of a Green Roof Chicago City Hall Sourcewwwaslaorgmeetingsawardsawds02chicagoci t hallhtml

Page 4


are best applied The benefits such as SWM (storm water management) Energy Saving Heat Island Reduction Environmental (habitat) Green space etc are described in subsequent sections of this report

For the City of Waterloo the potential use of Green Roof technology will be defined by its needs itrsquos suitability itrsquos environmental sensitivity and itrsquos economic viability Of the primary environmental benefits offered by Green Roofs (SWM pollution mitigation energy conservation heat island reduction green space) it is expected that SWM will form the majority of the potential motivation for its use Unlike the City of Toronto or Chicago Waterloo is comparatively not as highly industrialized or as densely populated thus the pollution mitigation potential of Green Roofs for Waterloo will likely be less justifiable Waterloo is comprised of highly impervious areas in the core and high density residential at the outside core For this reason storm water management becomes a significant concern by the local conservation authority and development control bodies This is in large part for the protection maintenance and possible improvement of the Cityrsquos creeks rivers and lakes and hence fishery resources Green Roofs also offer social and economic benefits such as extension of roof life improved aesthetics and opportunities for urban agriculture These benefits or opportunities are lsquobuilt-inrsquo with the technology regardless of the objective and help to reinforce the rationale for their use The benefits are far reaching thus it can be said that they provide a lsquochain of benefitsrsquo see Figure11

12 Study Objective

The intent of this study is to identify which municipal buildings would be most suitable for a Green Roof system to analyse the potential benefits and to identify the costs associated with construction operation and maintenance

This feasibility study includes the selection and development of a demonstration site to showcase a potential Green Roof installation It will mark the first municipal Green Roof installation in the region Together with a selected demonstration site a preliminary concept will be prepared to detail the Green Roof installation The concept includes an lsquoImplementation Planrsquo to assist in the realization of the Green Roof demonstration site An implementation plan has also been devised to provide a template for a Green Roof program on other City owned buildings

20 GREEN ROOF DEFINITION

Since Green Roofs vary in composition vegetation types imposed loading applied locations extent of coverage etc and corresponding benefits a Green Roof definition needed to be tailored specifically for

application to Waterloo with consideration of their lsquoEnvironment First Policyrsquo

Green Roofs represent an opportunity to mitigate the adverse environmental impacts of urbanization and development by placing vegetation on the rooftops of commercial industrial institutional residential and a variety of other building types

For a lsquoGreen Roofrsquo to be installed on a building it needs a root and water barrier a medium to grow plants and be low in maintenance requirements The variety of planting and growing mediums available can allow for a Green Roof to exist on either existing or new buildings of

Green Roofs can be installed on a variety of roof configurations including slopes roofs Source wwwxerofloracom

varying roof slopes See Appendix L

Page 5

connectivity to airborne

species

Energy Usereduction

Reduction of Heat Island

Stormwater Management

(SWM)

Increase in Green Space

Extension of roof life

Air pollutionreduction

Improved water quality

Reduced runoff

volumes

Cleaner air Reduction in

poor air related

Reduction in health costs

Cooler ambient air temperature

Reduction in cooling energy

Reduced loading on

hydro power

Reduced heat loss

Increased aesthetic

urbanscape

Increased consumption

of insects

Reduced potential for

airborne

Protects underlying roof system

Reduced erosion in

creeks

Improved fish habitat

Reduced consumption of fossil fuels

Reduced temperatures

In runoff

Opportunity to optimize storm sewer

Reduced storm sewer

costs

Reduced use of man-made

materials

Reduction in creek

maintenance

Reduced heating and

cooling costs

Reduces costs of

future roof

GREEN ROOF TECHNOLOGY ndash CHAIN OF BENEFITS Figure 11

Definitions SWM the method used to mitigate the impacts of storm water runoff resulting from changes in land use Heat Island An area of concentrated increased air temperatures resulting from surfaces that radiate accumulated solar heat energy Green Space An area of vegetative cover that improves urban aesthetics


What is a Green Roof

For the City of Waterloo a Green Roof is a system of plants growing medium and root waterproof membranes that act as a whole to maximize the available environmental benefits on the roof of any type of new or old building

A lsquoGreen Roofrsquo is a Green Roof if it improves air temperature air pollution storm water and green space The primary objective for a Green Roof is environmental enhancement although recreation and other uses may be available in some Green Roofs

It should be noted that the word lsquogreenrsquo in Waterloorsquos case signifies environmental sensitivity and includes all facets of what environmental sensitivity implies In lsquoroof gardenrsquo instances lsquogreenrsquo refers more to planting or soft landscaping thus the word green should not be confused with the colour of the cover rather the attributes that serve to enhance the environment

For the purposes of this study an idealized representative Green Roof will be used in determining benefit potential Sufficient data is currently available to predict quantification of Green Roof benefits within a reasonable tolerance With the understanding that Waterloorsquos greatest Green Roof needs occur in the already developed uptown core it is safe to note that the majority of potential Green Roof systems will be of the retrofit type that is a light weight system of growing medium and planting that can be adapted to existing roof structures with little or no structural reinforcement This system can be referred to as an lsquoextensiversquo Green Roof which not only satisfies the Waterloo Green Roof definition it also provides a conservative estimation of Green Roof qualities An explanation of the different Green Roof types is included in Appendix M

The representative lsquoextensiversquo Green Roof system will consist of bull Waterproof membrane bull Root Barrier bull Drainage layer bull Growing Medium bull Vegetation

This system would include the following performance characteristics bull Storm water retention capacity 37 litresm2 bull Air pollution removal potential 02 Kg per m2 per

year bull Energy conservation lsquoRrsquo value 5 (est) bull Temperature Absorption up to 18degC degrees

(compared to gravel roofs) bull Saturated Weight 9 to 12 psf

Example of an lsquoExtensiversquo Green Roof Source wwwxerofloracom

Filter Cloth

Source American Wick Drain Corp

Page 6


30 FEASIBILITY APPROACH

To determine if Green Roofs are feasible in Waterloo it must first be determined if the needs actually exist to justify their use Areas of investigation need to extend to cover the environmental benefits of Green Roofs and to determine if Waterloo can make purposeful use of these benefits The benefits are listed below followed by an estimation of the need for the benefit and other currently used comparative methods (within Waterloo) to mitigate those needs Feasibility also implies cost effectiveness that is if the City currently uses more cost effective methods of mitigating environmental impacts Green Roof technology would be difficult to justify It should also be noted that as the Green Roof industry progresses in North America designers suppliers and installers will respond with being able to provide the technology at lower costs

Potential Green Roof Benefits

Primary Benefits

1 Storm Water Management (quantity quality erosion control) 2 Air pollution reduction 3 Energy conservation 4 Reduction of lsquoHeat Islandrsquo 5 Provision of Green Space (aesthetics and recreation) 6 Connectivity to natural airborne species (environmental) 7 Urban Agriculture

Secondary Benefits

1 Noise Reduction (one or two story buildings benefit diminishes with increased building height) 2 Extension of roof membrane life 3 Horticultural Therapy (applies to lsquointensiversquo type green roofs only) 4 Possible increase of fire rating for roof assembly (when properly maintained Green Roofs may

extend length of fire rating in terms of time Some Green Roof manufacturers provide fire certification based on maintenance of minimum moisture conditions)

31 Storm Water Management

Storm water management (SWM) is a term used to describe the control or management of discharge and runoff resulting from rainfall on a specific area or areas Urban centres make wide spread use of storm water management since the increased areas that are impervious to rainfall infiltration such as roofs roads parking lots etc cause an increase in runoff Eventually a portion of the rainfall accumulation ends up in a watercourse or lake system The receiving watercourse or lake system not being easily adaptable to the increase in runoff responds by eroding degradation of habitat areas exceedance of conveyance capacity and possible flooding

The purpose of storm water management is to attenuate the increased runoff to levels and conditions that the receiving watercourse is capable of handling most often referred to as lsquopre developmentrsquo levels The difference in accumulated runoff between the post development level and predevelopment levels must be stored treated and discharged at a controlled rate of volume and duration There are several ways to store and treat rainfall discharge The following section of this report outlines the current methods of SWM and demonstrates how Green Roof technology can be an effective SWM control method This section also describes how SWM can protect maintain and improve the City creeks

Page 7


Storm water management can be subdivided into the following categories bull Water quantity control bull Water quality control (suspended solids nitrate phosphorous bacteria and temperature) bull Erosion control

It is important to note that SWM controls are available in three basic methods at source end of pipe and conveyance At source controls are preferable because it deals with storm water before it is concentrated into a conduit and conveyed to an outlet This reduces the storm system costs as well as end of pipe mitigation requirements such as erosion control

311 Common methods of controlling the storm water effects of new development

bull SWM ponds bull OilGrit Separators bull Traditional roof top storage bull Infiltration trenches

SWM ponds Storm Water Management Ponds have been in place for many years SWM ponds traditionally use valuable development real estate and function to temporarily impound storm water and release it at a controlled rate1 Within the recent five years the Ministry of the Environment has imposed a requirement to control erosion in ponds this is accomplished by up-sizing the facility beyond the lsquoquantity and qualityrsquo requirement and discharging the flow through an orifice sized to the maximum calculated allowable volume or lsquoerosion thresholdrsquo determined for any given watercourse The quality function much like the erosion function is handled in terms of pond sizing SWM ponds generally do not improve (lower) temperatures on the contrary most current designs will tend to increase temperatures Emerging concerns over West Nile Virus potential in standing water also put in question the function of SWM ponds with regard to public health

OilGrit Separators Oilgrit separators (OGS) are used to trap and retain oil andor sediment in detention chambers usually located below ground2 They operate based on the principles of gravity-based sedimentation for the grit and phase separation for the oil

Separators may be used as spill controls pre-treatment devices or as a sourceend-of-pipe controls (as part of a multi-component approach) Oilgrit separators are typically used for small drainage areas (lt 2 hectares) and generally form part of the underground storm sewer infrastructure Their use is typically not constrained by space considerations bedrock or groundwater levels or soil conditions

When compared to the SWM function offered by Green Roofs OilGrit separators do not offer quantity control and hence no peak flow reduction potential They are however one of the few options for quality control on already developed sites since they impose minor spatial requirements They are also not purely lsquoat sourcersquo control as are Green Roofs since they collect storm water after it has discharged from the catchment area

1 List of CSOStormwater Control Alternatives 2 List of CSOStormwater Control Alternatives

Page 8


Rooftop Storage Flat building roofs can be used to store the rain that falls on them and to reduce peak flow rates of runoff to storm sewer systems3 Rooftop storage has been used for several decades as a peak flow (quantity) control There are few water quality erosion control or water balance-type benefits achieved by utilizing this type of storage on building roofs However site servicing and storm drainage costs may be reduced through reduced downstream storm sewer sizes

Traditional rooftop storage is applicable to large flat commercial and industrial rooftops only and in some cases residential apartmentcondominium developments Rooftop storage is widely applied for infill development scenarios to mitigate the need for downstream storm sewer size increases This control storage functions to reduce downstream peak flow rates The volume of storm runoff to the sewer system however is not reduced as discharge occurs over a much longer duration

It can be suggested that traditional rooftop storage will discharge over 95 of the volume accumulated in contrast the lsquoevapotranspirationrsquo mechanism that Green Roofs provide essentially allows the accumulated storage to be utilized by the vegetation and results in an effective discharge of less than 20 in many installations This is a major benefit improvement over conventional systems Also in contrast to traditional rooftop storage Green Roofs offer quality control potential by filtration through the vegetative and component layer assembly

Infiltration Trenches Infiltration trenches can be used to reduce peak flow rates in receiving systems reduce total volume of runoff from a given event and contribute somewhat to quality improvement by reducing atmospheric pollutants through natural filtration4 They use grasses or other vegetation to reduce runoff velocity and allow filtration while high volume flows are channelled away safely Water is detained in the infiltration trench until it either evaporates or infiltrates This method is seldom possible since typically local soil conditions do not allow sufficient infiltration rates and requires large areas to be used In urban areas space is limited and generally cannot accommodate these methods

Infiltration trenches are favoured methods of SWM control since they also potentially help to recharge ground water These methods can be used in conjunction with Green Roofs as a secondary control

312 Common methods of controlling the effects of existing development

bull Creek Rehabilitation bull OilGrit Separators (described above) bull Cisterns

Creek Rehabilitation Creek Rehabilitation refers to changing channel andor valley form by direct intervention to mitigate a disturbance that is causing instability Modifications may include changing the course of a river the channel dimensions or the character of the channel Creek rehabilitations can create a more stable channel in cases where the channel has been straightened or in cases that involve a change in upstream inputs Recently creek rehabilitation has been used by some municipalities as an option for storm water management in fully developed areas where alternative methods are not possible This can include varying degrees of rehabilitation depending on the SWM requirements Flood control can be achieved by creating storage areas within the creek system as well as quality control through use of stilling basins and vegetative treatments


Page 9


Creek rehabilitation is categorizes as lsquoconveyance system controlrsquo treating flows after they have concentrated A watercourse can only be viable as a method of SWM control if sufficient spatial allowances permit In many urban settings creeks are generally constrained and offer little opportunity for flood control re-configuration thus this method is not always an option Green Roofs are considered lsquoat sourcersquo controls and provide storm water management prior to discharge into storm sewer systems and watercourses thus they and can in effect reduce the potential maintenance or rehabilitation requirements on a SWM facility or watercourse

Cisterns Cisterns can be used to store rainwater temporarily as a method of SWM Approximately 15 years past the City of Waterloo had standard details for cistern design however through monitoring it was decided to discourage further use of the system due to water quality issues Issues arose due to infrequent flushing and caused water to stagnate Cisterns however can be used in conjunction with Green Roof systems both as a secondary water quantity and quality treatment as well as a source for irrigation of the Green Roof during dry weather conditions lsquoRecyclingrsquo or re-use of the water retained in cisterns thus would reduce the probability for water quality issues resulting from stagnation

313 Potential water quality improvements in City Watercourses

Any development site located within a flood line or fill line of any watercourse is subject to review by the local Conservation Authority in Waterloo itrsquos the Grand River Conservation Authority Traditionally conservation authorities have been concerned with ensuring that flooding is controlled within their jurisdiction this entailed the required submission of a permit to alter or build within a regulated flood zone Current conservation authority practice extends well beyond the control of flood zones In conjunction with efforts from the Ministry of Natural Resources and Department of Fisheries the conservation authority now actively participates in preservation of the natural environment in particular with fishery resources Any development activity that has the potential to alter the integrity and function of a watercourse must undergo review by the conservation authority In the case of storm water management any facility or drainage that discharges into a watercourse must be subject to the requirements set forth by the authority to maintain the quality of the watercourse For this reason it is an important consideration that Green Roofs have the potential to improve the quality of runoff and moreover to be considered a viable opportunity to control water quality from developed sites

The following is a listing of watercourses inventoried through the lsquoLaurel Creek Watershed Studyrsquo within the City of Waterloo5 These watercourses are located throughout the City and are all subject to urban runoff

Clair Creek Clair Creek is a warm water baitfish creek with poor warm water habitat siltation and elevated temperatures In areas there is significant erosion

Laurel Creek and tributaries There are some warm water sport fish however significant portions are chanelized including the underground portion of Laurel Creek (Uptown) Generally the creek is considered to be a poor quality warm water habitat There is excessive organic material and sediment and elevated water temperatures There is potential for Laurel Creek to be coldwater upstream of Wilmot Town Line Urban development has resulted in significant impacts on Laurel Creek particularly with respect to water quality

5 Laurel Creek Watershed Study 1993

Page 10

Page 11


Forwell Creek Forwell Creek contains warm water sport fish habitat with fair warm water habitat

Cedar Creek Water quality is generally acceptable to aquatic organisms

Beaver Creek Water quality is generally acceptable to aquatic organisms however there is excessive mulch and sediment There is a lack of suitable spawning substrate and the creek experiences elevated summer water temperatures This creek has the potential to be coldwater

Monastery Creek This creek could potentially provide coldwater habitat however the water quality is low and there is low benthic diversity To provide coldwater habitat it is critical to control sediment loads and temperature impacts

314 Flooding There are ten existing flood centres seven of which are located on Laurel Creek one each on Forwell Creek Cedar Creek and Clair Creek Increased stream flows will increase the risk of flooding downstream especially in Uptown Waterloo

General Recommendations of the Laurel Creek Watershed Study Information on Waterloo Creeks was taken from the Grand River Conservation Authority Laurel Creek Watershed Study 19936

- Flood risk be reduced in each of the ten flood centres - Institute water quality control in the existing urban areas - Initiation of a Master Plan process for green spaces systems - Storm water and land development control measures to ensure that any new developments do not

increase the existing levels of flooding - At source control measures should be given preference in selection of storm water management

facilities and existing drainage systems where possible - Redevelopment should be carried out in existing development areas in a manner which limits

increases in impervious areas - Runoff control measures be incorporated to ensure that stream bank erosion does not increase in

downstream sections ndash provide volume control - Specific steps to taken to maintain and increase the public profile of the recommendations in the

plan (ie storm water management greenspaces flooding)

The listing of creeks in the City has been done to demonstrate the diverse nature of aquatic natural resources that need protection as well as to determine the overall sensitivity of the creeks to storm water impacts Creeks are classified in terms of lsquowarm waterrsquo and lsquocold waterrsquo categories The classification of creeks into warm water and cold water relates to the level of water quality and temperature that the resident species can tolerate In warm water creeks


Rainfall volume runoff from a Green Roof is reduced and is cooler when compared to a conventional bare roof


warm water aquatic species can tolerate a wider range of water quality fluctuations as compared to cold-water species The presence of cold-water species is an indicator of good water quality That is that the conditions in the creek with respect to stability habitat (feeding hiding and reproduction opportunities) and water quality have the potential to sustain certain fish species which would demand those conditions If it is shown that a creek has high sensitivity to water temperature and water quality impacts then the requirement to protect these resources becomes important In summarizing the creek systems in the City the classification suggests that all creeks in the City are warm water thus meaning that the resident aquatic species have less sensitivity to impacts of storm water than would cold water species

Potential Impacts of Green Roofs and Creeks

All of the creek systems in the City have potential to improve water quality even though the classification does not mandate intensive resource protection it is important to note that the water resources are in need of improvement and that any effort to achieve lsquocold waterrsquo conditions therefore to improves improve water quality

Improved stormwater management for both quantity and quality would reduce erosion sedimentation and habitat in local creeks Green Roofs provide a unique storm water management opportunity particularly in the urban core where land is not available for traditional storm water management facilities

The following are the chain of benefits that Green Roofs can provide to creeks

Water Temperature Where Green Roofs offer tremendous benefits is in water temperature reduction High water temperatures cause creeks and ponds to form algae reduce water clarity and thus result in anoxic conditions The reduction of water temperatures will enhance water quality thus reduce potential for algae formation and promote conditions for a healthy benthic community A healthy benthic community will then attract higher quality aquatic species

Erosion Control Reduction in storm water runoff volume from Green Roofs will reduce flow velocity and duration hence reduce erosion on creek banks and creek beds The reduction in erosion translates to improved water quality since suspended soil material within the flow will be reduced This also improves creek stability and reduces the frequency of creek maintenance and rehabilitation

Water Quality Although some information exists on the performance of Green Roofs with respect to water quality further study needs to be done in order to better quantify how a Green Roof would meet the requirements of the Ministry of the Environment on storm water management Studies currently suggest that a high percentage of Phosphorous is potentially carried through air and may be co-related to suspended solids Pending further study water quality improvements can be added to the list of benefits that can be used to justify Green Roof implementation costs

32 Air Pollution Reduction

According to a May-June 2000 article in Canadian Geographic Kitchener Ontario was ranked number 1 (worst community) by the amount of ground-level ozone and number 5 by the amount of fine airborne

Page 12


particulate matter (based on 1998 data)7 Due to Waterloorsquos close proximity to Kitchener it could be inferred that Waterloo has similar air pollution concerns Approximately half of the ozone comes from the Ohio Valley and the Cleveland - Detroit areas therefore Kitchener and Waterloo must not only deal with their own pollution they must also deal with pollution imposed by other municipalities

The Ontario Medical Association states that the components of air pollution ldquopose a serious health risk to the people of Ontariordquo In particular fine particle matter poses the greatest effect on health Fine particulate matter consists of particles that are 25 microns or less in diameter (PM25) The particulates penetrate the respiratory system increasing the number of citizens requiring medical attention Sources of fine particulate matter include aerosols smoke fumes dust fly ash and pollen In the Air Quality in Ontario 2001 Report (published by the Ontario Government) Kitchener had fine particulate levels of 282gm3 8 Waterloo results can be considered similar to Kitchener due to the close proximity of the two cities The Canadian Council of Ministers of the Environment has developed Canada Wide Standards of 30 gm3 for PM25 Cities will have to meet this standard by 2011 with monitoringreporting to begin in 2006

Existing information on Green Roofs suggest that they can remove 02kg of particulate matter annually per m2 of Green Roof9 Although Waterloo has not exceeded the level of 30 gm3 for PM25 it does have one of the higher levels across the country (for example Toronto had levels of 292 gm3 3000gm3 and 347 gm3 for PM25) Current information also suggests that 30 of the phosphorous source is airborne thus Green Roofs have the potential to reduce phosphorous

Improvement to air quality resulting from the use of Green Roof technology is difficult to quantify and further research is required The benefits would clearly suggest that better air quality would result in reducing the frequency of public needing medical assistance thus lessening the load on the health system Pollution reduction can also result from reduced energy consumption due to lower energy demands on the power producing facilities

33 Energy Efficiency

Green Roofs offer improved energy efficiency in roof systems in two ways One way the insulation factor is easily measured The roof medium provides a thermal break from the structural portion of the roof and can be enhanced with the addition of a specific insulation layer The second way relates to the heat island effect and is less quantifiable This occurs as a result of the vegetative layer having less heat gain than gravel or concrete surfaces Alternative Green Roof system assemblies will each have their own insulation qualities the deeper the medium the better insulation potential Due to our seasonal changes the winter months will result in a freezing of the Green Roof system this renders the insulation factor as minimal since the air spaces are not longer acting as a thermal break For this Heat loss is reduced through a building roof and heat gain

is reduced from solar radiation meaning improved energy efficient and lower outside air temperature

7 Canadian Geographic May-June 2000 Blowinrsquo in the Wind Ontario Government 8 Air Quality in Ontario 2001 Report Ontario Government 9 Green Roofs For Healthy Cities httpgreenroofsorgindexphppage=publicbenefits

Page 13


reason the energy efficiency offered by Green Roofs in the winter is drastically reduced when compared with cities that endure less frequent freezing conditionsOne way to quantify Waterloorsquos energy consumption with respect to other Cities is to examine the effects of the local climate on energy consumption The best metrics to use for comparison are the heating degree days and cooling degree days (DD)

For example

10Waterloo Annual Heating DD (below 18 C) = 4288 Mean Temperature = 67 C Ottawa Annual Heating DD (below 18 C) = 4602 Mean Temperature = 60 C Windsor Annual Heating DD (below 18 C) = 3525 Mean Temperature = 94 C

The annual energy consumption for a building is roughly proportional to the number of degree days Therefore we would expect the heating energy consumption for a building in Waterloo to be about 93 of a similar building in Ottawa It would be about 122 of a similar building in Windsor

As part of the feasibility study the energy consumption impacts of a Green Roof on a building were quantified In summary a Green Roof offers minor savings in building energy consumption due to the following

Space Heating Space Cooling Lighting Service Water Heating Other

Source Model National Energy Code for building (MNECB) for Ontario

Annual Energy Consumption Summary (1-Storey MNECB Reference Building)

49

7

4

21

19

1 Heating only makes up 50 and space cooling makes up 7 of a buildingrsquos energy use The remaining uses - lighting (21) service water heating (4) and miscellaneous (19) cannot be impacted by Green Roofs Therefore a maximum of 57 of the buildingrsquos energy use consumption can be impacted The walls windows and basement in a building

generally account for the majority of potential heat loss2 Green Roofs can only improve energy efficiency on Energy efficiency through roof losses is limited the roof losses still occur through the walls windows and basement

3 Green Roofs are most effective at decreasing heat loses during spring and summer During the winter the Green Roof medium freezes and provides little insulation value

Although decreased energy is a benefit solely it could not justify construction of a Green Roof With respect to other cities and energy consumption a Green Roof in Waterloo would be less beneficial than a Green Roof in Windsor (due to Windsorrsquos warmer climate) more beneficial than one in Ottawa (due to Ottawarsquos colder climate) and about the same as Toronto (generally the same climate) A complete energy analysis can be found in Appendix D

10 Annual Heating Degree Days Environment Canada

Source Heat Island Group

Page 14

City of Waterloo ndash Thermal Image Figure 34 TH

ERM

AL G

RAD

IEN

T

HOT (HIGH TEMP) HIGH TEMPERATURE DELINEATION AREA

APPROXIMATE CITY OF WATERLOO BOUNDARY

COOL (LOW TEMP)

chuxted
FES Mapping Analysis amp Design13University of Waterloo


34 Urban Heat Island

On warm summer days the air temperature in urban areas can be several degrees higher than in the less urbanized areas this is known as the Urban Heat Island (UHI) The increased temperature is largely due to the increased amount of paving or roofing (dark surfaces absorb more heat from the sun) and reduced vegetative cover that can normally provide heat attenuation The increase in air temperature results in an increase of energy consumption due to increased use of cooling equipment in turn increasing demand on hydropower increases pollution cause by power generating stations through burning of fuels

To date limited information is available regarding UHI in Waterloo or in the Waterloo Region In general cities with populations greater than 50000 are subject to UHI11 The following formula can be used to determine the maximum heat island

Maximum Heat Island = 201 log P ndash4060C12

Where P = Population = 102300 for the City of Waterloo

Maximum Heat Island = 6010C

This value does not necessarily indicate that the urban core in Waterloo is 6010C higher than the non-urbanized area since the increase depends on several factors including density wind speed land use etc however the potential exists

Limited information exists on the impacts of Green Roofs on UHI but there is a general indication that increased vegetation decreases air temperature Green Roofs provide an increased overall vegetated urban surface area and have the potential to decrease UHI by an amount that has not yet been determined Curbing UHI in Waterloo is a potential benefit of a Green Roof however quantification of the cooling effect at this time would prove difficult A thermal image of the City of Waterloo is illustrated on Figure 34 this figure shows the range of temperatures across the city

35 Green Space

Green Space a component of urban planning for any development is based on building area and occupancy subject to a Green Space policy and a set of requirements To define lsquogreen spacersquo reference must be made to planning standards it is acknowledged that Green Roofs certainly offer green space potential however generally green space is required to be seen or exposed to public view For Green Roofs the simple virtue that the green space would be located on roofs and out of public site negates the benefit Where the visual is realized is when a Green Roof can be seen by vantage points that are located higher than the installed roof The City of Toronto holds a good arena whereby Green Roofs can be seen by public on a regular basis With the high density of urban buildings in Toronto or any other major City Green Roofs could potentially cover a significant percentage of areas that can easily

11 Stephen Peck Green roofs for Healthy Cities 12 Vegetation and Climatic Changes in a City Ecological Engineering

A comparison between the temperature of gravel surfaces and a Green Roof indicates that a Green Roof surface is significantly cooler and closely matches the air temperature Source xerofloracom

Page 15


be seen by the public using them For Waterloo very few perspectives are available to view Green Roofs (ie Marsland Centre Allen Square Parkade) therefore to put forth the suggestion that Green Roofs can offer green space attributes in Waterloo further study is required however some opportunity exists Possible future developments may increase the opportunities for viewing Green Rooftops

36 Connectivity to Airborne Species (Habitat)

Current development control practices serve to protect the environment and to preserve natural features especially in the event that sensitive or rare species are present Watershed studies Environmental Assessment studies and specific scoped studies are used to establish development limits based on the surroundings For past urban development these controls were not in practice The downtown core of most cities is largely covered with impervious surfaces roadways parking lots buildings etc in order to maximize occupancy It is in these areas that natural surfaces are most needed to provide habitat or rest areas for airborne species

Green Roofs can provide shelter food (from seed bearing plants) and shade to a multitude of airborne species such as birds and butterflies Some Green Roof installations have been specifically design to provide habitat for butterflies this not only attempts to re-balance the urban natural habitat loss it also re-connects nature to an otherwise isolated human habitat

In todayrsquos era issues such as West Nile rise to awareness Public concerns with potential West Nile breeding grounds often act to remove wetlands and other natural features which ironically are designed to harbour habitat for species that consume West Nile carrying insects Ill controlled urbanization is in part responsible for the lsquounbalancersquo in the environment Green Roofs offer an opportunity to re-establish a balance in the function that natural features of a particular area once performed It is difficult to quantify the net effect or benefit of re-establishing green landscape to urban landscape in terms of West Nile reduction potential or bird habitat however any added natural landscape can provide a potential improvement

37 Extension of roof life span

Canadian climate cycles require that our infrastructure be designed and constructed with special consideration to temperature changes This affects most exterior structures buildings roadways

Foundations require frost protection due to the potential differential movement of soils during freezing temperatures thus structures must be designed either to avoid temperature impacts or to expand and contract according to the given temperature ranges that they may be exposed to Typical temperature ranges extend from ndash40 degrees Celsius to +40 degrees Celsius within this range materials expand and contract by up to 10 of their original size depending on the type of material On building roofs concrete surfaces will have dissimilar expansioncontraction coefficients compared to adjacent

surface materials however these materials such as bitumen Source xeroflora com

sewers etc

(asphaltic coating) and membranes are flexible and have a higher rate of change As conventional roofing materials are exposed to solar radiation over time the elasticity of the materials are reduced and eventually fail to respond to temperature changes resulting in cracking Green Roofs offer protection to conventional roofing surfaces from solar radiation (ultra violet) and other weather conditions and in effect act to significantly reduce surface degradation as well as reducing the expansioncontraction cycle Existing data suggests that Green Roof systems can extend

Page 16


the life expectancy of conventional roofs by a factor of 2 to 313 With the potentially reduced rate of roof membrane replacement some additional cost savings may be possible resulting from the reduced volume of roof landfill waste

38 Urban Agriculture

The World Dictionary defines Urban Agriculture as ldquo the practice of agriculture (including crops livestock fisheries forestry and activities) within or surrounding boundaries of citiesrdquo The land could be private or non-private and could be ground based or on walls balconies and roof tops Urban Agriculture can increase the amount of food available to people living in cities and can allow for availability of fresh fruit and vegetables to urban consumers Greens Roofs can provide the opportunity to accommodate Urban Agriculture space on building roof tops The type of Green Roof required for this use however is generally of the lsquoIntensiversquo variety This requires that sufficient roof load capacity be available to support the medium required to grow food producing plants Very few opportunities exist to accommodate lsquoIntensiversquo Green Roofs within the existing municipally owned buildings in Waterloo (Parkade Building) Possible future buildings may be designed to provide the required loading for Green Roof uses such as Urban Agriculture including private developments on Condominiums Offices and Senior Centres Institutional buildings such as hospitals may also provide a good opportunity Urban Agriculture and in turn provide horticultural therapy

40 CITY WIDE IMPLEMENTATION PLAN

The City Wide implementation plan is intended to consider the municipal building candidates identified in the building selection process and prioritise them firstly on the greatest potential for optimisation of the listed Green Roof benefits The prioritisation will then need to be assessed according to the roof replacement budget allowance timing that has been set A building assessment template can be used to determine which Green Roof type best suits an individual site See Figure 40

The approach to determining a City Wide implementation plan uses the optimization of the major Green Roof environmental benefits that can be applicable to the City of Waterloo A map of the City was created to demonstrate the focus area for each benefit offered by Green Roofs Superimposing all of the focus areas on a single map will identify the area of concentration where the need for Green Roofs is the greatest Using the colour red to delineate each benefit focus area where locations overlap a darker colour results therefore the buildings that lie within the darkest colour red are the buildings with the highest priority for a Green Roof installation as the colour becomes less dark the priority decreases

The following Green Roof environmental benefit need areas were mapped

Storm water Management

Figure 401 shows the delineated area where Green Roofs would best improve storm water management The area was determined based on bull The likely location of the oldest or outdated storm systems that would best benefit from runoff

reduction bull The highest concentration of impervious area bull The least likely location for any alternative method of storm water management (ie

insufficient space for pond construction)

13 The Greenroof Industry Resource Portal wwwgreenroofscomeconomichtm

Page 17

City of Waterloo Building Assessment Template Figure 40

STEP 1

Identify green roof building candidate and verify roof replacement timing schedule

Assemble any available design and construction information about roof

Determine if old roofing surface requires removal

STEP 2

Based on the load capacity existing roof in place or existing roof removed select a green roof type

STEP 3

Prepare roof plan amp details

STEP 4

Select appropriate plant species from City approved list

Determine requirement for irrigation based on plant species

10 psf to 35 psf (50 kgm2 to 170 kgm2)


60 psf or greater (290 kgm2)

Less than 10 psf

Conduct field measurements and surface elevation survey

Determine extents of green roof coverage

Conduct a structural assessment to obtain a roof load capacity estimation

Select lsquoExtensiversquo

Option to use lsquoExtensiversquo or lsquoSemi Intensiversquo

Option to use lsquoExtensiversquo lsquoSemi-Intensiversquo or lsquoIntensiversquo

Determine requirements for structural reinforcement

Determine drainage patterns and existing roof drain capacity

Refer to manufacturerrsquos drainage capacity requirements

Forward drawings grades loading and plant list to a green roof supplier and request quotation

Apply for building permit


bull The areas most likely to adversely impact water quality in creeks

Energy Efficiency Figure 402 shows the delineated area where the highest concentration of older buildings in Waterloo are situated These buildings will likely have the least energy efficiency since energy consumption was not a concern in the era that they were constructed These buildings can best make use of the energy saving benefits of Green Roofs

Urban heat Island Figure 403 shows the delineated area where it is expected that surface heat is of highest concentration This area is similar to the SWM area since the heat island effect is primarily caused by impervious surfaces such as parking lots roofs thermal mass building colours and materials etc

Pollution Figure 404 shows the area where pollution is likely to be highest and is based on the concentration of industrial uses and vehicular traffic rates This area also have a lesser ability to dissipate polluted air due to the restricted movement of air

Green Space Figure 405 shows the area where green space is currently scarce and has the potential to be augmented through the use of Green Roofs This eligibility is in part due the view perspectives that are available from tall buildings with public occupancy that could benefit from the view

Of all the benefits Green Roofs can potentially offer the City of Waterloo the buildings that lie within the intersection of all these benefits result in developing the order of priority of implementation

Using the colour concentration method the following buildings are prioritised for Green Roof implementation See Figure 406

1 Waterloo Public Library 2 City of Waterloo City Hall 3 Parkade 4 Adult Recreation Centre 5 Lions Lagoon 6 City of Waterloo Service Centre

(buildings 1 to 4 show equal priority ndash these buildings need to be further prioritised based on budget and timing)

Table 401 City Wide Implementation Plan

Building Name Maintenance fund timing

Maintenance budget allowance

Roof Area (Approx m2)

Estimated total cost for Green Roof Installation (before taxes)

Waterloo Public Library (Demo Site)

2007 2012 $16400000 $1800000(LOT)

2200 $33000000 plus access (approx $6000000)

City of Waterloo City Hall

2005-2006 $25000000 2800 $42000000

Adult Recreation NA NA 740 $11100000

Page 18


Centre Lions Lagoon NA NA 370 $5550000 Fire Dept Headquarters

NA NA

City of Waterloo Service Centre

2008 $38800000 4350 $65250000

Fire Hall Sta 2 NA NA 444 $6660000 MS Arena 2012 $20000000 2850 $42750000 WMRC 2013 $30000000 3200 $48000000 Cemeteries (parkview)

NA NA 320 $4800000

RCAFA Rotary Adult Centre

NA NA NA NA

Access costs include stairs railing and related components for proposed demonstration site only

41 City wide Program

The benefits of Green Roof applications from a city wide perspective are bull Storm water management bull Air pollution reduction bull Energy conservation bull Reduction of ldquoheat islandrdquo effect bull Provision of greenspace bull Environmental habitat (airborne species) bull Extension of roof life

From a city wide perspective the overall benefits with respect to the ldquoheat islandrdquo reduction greenspace and environmental habitat increase in their perspective through the cumulative effect of a larger number of facilities over single facilities

Program opportunities Priority Areas The opportunities for green-roof applications across the city vary depending upon the density of development and the type of rooftops as well as the potential for improvement to the surrounding environment or receiving system (ie streams) This is discussed in section 40 of the report Green Roof installations are most easily applied in areas of larger flat rooftops although applications can be placed in sloped rooftops of up to 45 degrees The greatest benefit will be realized in areas with the most dense coverage of relatively flat rooftops (ie such as commercial and industrial areas) for the following reasons bull This is typically the area with the highest ldquoheat islandrdquo effect as a result of high coverage of

rooftops and paved areas bull The greatest benefit to the receiving system will be received since these are typically the

areas of highest runoff impacts (ie poorest water quality and greatest erosion impacts) bull These are the areas with the least coverage of ldquogreenspacerdquo (and correspondingly the

greatest demand for passive use)

The highest priority areas for Green Roof application is therefore the areas of highest concentration of relatively large flat rooftops (see Figure 401)

Green Roof applications however can be distributed across the city based upon the willingness of property owners to participate

Page 19


Municipally owned buildings provide an opportunity as demonstration sites for showcasing aspects of the Green Roofs that could include education technology development and environmental benefits

42 Programs in other Areas

There is a growing number of municipalities that are providing incentive programs to encourage the installation of Green Roofs to achieve the overall benefits (as described in this report) The primary barrier to Green Roof application is the greater initial cost over a conventional roof system In addition much of the benefit that is realized with a Green Roof system is not quantifiable

Green Roofs have been used extensively in parts of Europe for several years Germany is considered to be a leader in the field with 14 of the total flat surface area in the country covered by Green Roofs Germanyrsquos Green Roof industry is largely the result of storm water concerns particularly for cities discharging to the Rhine Over 950 reports have been compiled on Germanyrsquos Green Roof industry The success of Germanyrsquos Green Roof industry is in part due to Green Roofs incentives Seventy-six municipalities offer various Green Roof incentives In some parts of Germany new industrial buildings must have Green Roofs by law The City of Stuttgart for example boasts 20 Green Roof coverage due to grants and their policy of Green Roof procurement Stuttgart has a budget of $78000 for roof greening and the City will pay for up to 50 of Green Roof costs to a maximum grant of $28m2 This program has resulted in the installation of 100000m2 of Green Roofs on public buildings and 46000m2 on private building14

Examples of incentives of other German cities are as follows

bull Munster offers 80 reduction on itrsquos rainwater tax for Green Roofs ($055m2yr) bull Cities on the Rhine (Cologne Bonn Mainz and Mannheim all have tax incentives bull state of Nordrhein-Westfalen pays euro1500m2 for Green Roofs bull Esslingen pays 50 of Green Roof costs bull Darmstadt covers all costs up to euro5000 bull Bonn ndash reduces an individualrsquos City water fees by euro075m2

bull Cologne and Mannheim decrease water fee by 50 (Cologne requires a minimum of 3rdquo of substrate)

Green Roof applications are not limited to Germany however Germany is considered to be a leader in the field In Swiss cities regulations now require new construction to relocate the area of greenspace covered up by the buildings footprint to the rooftop - and even existing buildings some hundreds of years old must convert 20 of their roofspace to pasture15

Although Green Roofs are more prominent in Europe they are beginning to emerge as a new industry in other parts of the world including North America Portland Oregon is considered to be one of North Americarsquos leaders in Green Roofs and Portland Oregon was the first City in North America to develop a Green Roof incentive program

Portland has an area of 135mi2 population of 500000 and their rooftops account for 40 of all impervious surface in the city The major reason for implementing Green Roofs in Portland is for storm

14Green Roofs in Germany Yesterday Today and Tomorrow 15 Swedish Green roof Initiative The Green Roof Society The International Green Roof

Page 20


water management Portland offers a density bonus to private developers as part of the Floor Area Ratio (FAR) or density bonus which affects an area of 3500 acres of 5 of the Cityrsquos total area The density bonus is 3ft2 of additional developmentft Green Roof provided that at least 60 of the area is greened Portland has designated 9mi2 for developers zoning bonus applications

Portlandrsquos Green Roof program is also tied into their storm water management program The city requires storm water runoff to be managed on-site and Green Roofs meet this requirement Portland is also planning to offer discounts to residents with Green Roofs through their storm water utility however issues with the billing system have stalled implementation until 2005 The City also provides grant funds for demonstration sites as well as additional funds for constructing a Green Roof on an existing office building

Other North American cities are also developing incentive and policy programs Toronto has advocates Green Roofs in their official plan Atlanta has proposed credits for Green Roofs through the storm water management utility with planned 2004 implementation16

Some cities have not yet developed Green Roof policies or incentives however they are publicizing Green Roofs through installation of demonstration sites (Vancouver Ottawa Toronto) Although there isnrsquot a specific Green Roof policy in Vancouver the city has been using Leadership in Energy and Environmental Design (LEED) certification as an incentive and they are moving to adopt LEED as a voluntary designationaccreditation for developers LEED is a non-government rating system for new construction and extensively renovated buildings Environmental criteria have been developed with respect to energy and water savings environmentally friendly building materials etc A builder basically receives a ranking on how environmentally friendly the building is Although LEED is voluntary at this time the incentive to developers to design LEED buildings are marketing (an environmentally friendly building is an incentive to some buyers) and lower storm water energy and water supply costs Some states in the US are considering enforcing LEED for certain sized projects and Portland requires that new public buildings meet certain LEED ratings Use of Green Roofs can account for up to 9 points and contribute to potentially 6 more if fully integrated with other building systems (Refer to Appendix O for further information concerning LEED)

In summary there are several Green Roof incentive programs being implemented throughout the world

bull lot level SWM fees bull density bonusing bull green space allocation bull tax credits bull energy efficiency incentives bull Storm water rebate or fee reduction bull Direct incentive bull Green procurement by government facilities bull Regulatory measures bull LEED (Leadership in Energy and Environmental Design)

43 Costs and Benefits

16 City of Atlanta Greenroof Demonstration Project

Page 21


A detailed evaluation of the costs and benefits associated with the proposed demonstration site are outlined in section 106 The analysis demonstrates that with contributions applied the Green Roof application provides a quantifiable benefit over a conventional rooftop application The relative costs and benefits of an application can vary from building to building depending upon the type of application and particular site conditions Typical costs and benefits and the factors that can affect them are outlined as follows

bull Green Roof Application

The application of a Green Roof will vary significantly depending as to whether it is an intensive or extensive rooftop application In addition rooftops can be used for a large variety of application such as vegetable gardens or any other types of garden plants In some applications this has been used as a source of revenue (ie herb garden at the Vancouverrsquos Fairmont Waterfront Hotel which produces $25000 to $30000 CND worth of herbs per year)

Typical Green Roof applications $100m2 to $250m2

bull SWM Benefit

As outlined in section 24 the SWM benefit is quantified in terms of the offset cost of having to install a SWM facility (at $42m3) The volume provided by a rooftop application can vary depending upon the depth of storage provided

Typical range in SWM value (based on depth of medium $2m2 to $25m2

thickness ranging between 5cm to 60cm)

bull Energy Benefit

The benefit in reduced heating and cooling costs will range significantly depending upon the type of building number of floors current insulation and condition of the building A typical analysis is provided in Appendix A

bull Value as greenspace (City of Waterloo)

If useable greenspace is provided typically as passive use only (ie benches walkways etc) The value of creating useable greenspace can therefore be equated to the value of passive parkland

Value as greenspace $15m2

bull Breakeven Costing

In looking at the costs of Green Roofs as compared to conventional roof systems the point at which the value of benefits need to be in order to provide the same overall cost is the breakeven cost

Capital and maintenance costs

The cost difference between the capital and maintenance costs of a conventional and Green Roof system taking into account the difference in initial costs and roof life based upon a present value cost (for a 50 year period) is summarized as follows

Page 22


Green Roof cost $16726m2

(assume $15000m2 capital $200000 annual maintenance cost (for a sample 1600m2 roof) and 50 year life span ndash 07 interest) Conventional Roof $7968m2

(assume $6000m2 capital $100000 annual maintenance cost (for a sample 1600m2 roof) life span half of Green Roof ndash 07 interest

Difference $8758m2

With the SWM benefit set at $2m2 to $ 25m2 and greenspace value at $15m2 including the higher cost associated with capital and maintenance the energy saving cost that would need to be realized per year to provide a breakeven cost scenario is

Energy saving needed to equalize Green Roof to conventional roof $61 to 84year per m2

44 Potential Partners

In considering the development of a city wide approach a number of interviews were held with various industrial and commercial representatives of the private sector This was carried out to identify if partnerships were possible and if there was any interest in participating or individual business owners installing their own Green Roof systems

Information obtained included the following

bull There is some interest in installing a Green Roof system on office building setting to provide for aesthetics and possible employee or tenant use This would only likely be done if a new roof is needed and if any structural modifications were minimal

bull Business indicated a willingness to donate funds to this type of program as a worthwhile endeavour

bull The development industry would like to see a credit made available for the SWM benefits associated with Green Roofs The installation of a Green Roof would only likely be carried out if the benefits matched the cost Intangible benefits would also be included in the consideration (ie aesthetics building valuemarketability)

50 PUBLIC INVOLVEMENT

The largest component of public involvement occurred during the public outreach (survey)

Public Outreach To fulfil the public outreach component of the study questions on Green Roofs were distributed as part of the Kitchener-Waterloo Metropolitan Area Survey 2003 The purpose of the questionnaire was to gauge public knowledge and interest in Green Roof technology as well as public interest in pursuing Green Roof technologies in the City of Waterloo

Several other agencies were involved in the survey with questions regarding pesticides community perceptions smoking in the workplace local food the environment politics and other socio-demographic related information The survey was distributed to random residents in Waterloo Region A copy of the survey is presented in Appendix B

Page 23


A summary of the responses received suggested that air quality was highest ranked in order of importance to the public followed by water quality Recreation ranked least important

The Workshop A Waterloo Green Roof Infrastructure Workshop was held in the Region of Waterloo on April 9 2003 The event was held by Green Roofs for Healthy Cities the City of Waterloo and the Region of Waterloo with additional sponsoring from Ontario Power Generation and CMHC-SCHL

The purpose of the workshop was to provide an opportunity to learn from local and national experts about the design and implementation of Green Roofs TSH and Enermodal Engineering presented ldquoDeveloping a Green Roof Strategy for Waterloo and the Surrounding Areardquo Afternoon breakout sessions (focus groups) allowed participants to identify local research needs and obstacles to implementation A copy of the workshop proceedings is included in Appendix C

Architectural week A presentation was given to a cross section of the public during Architectural week at the Waterloo Public Library The audience consisted mostly of students teachers and environmental advocates The presentation reviewed the benefits of Green Roofs and outlined the scope and intent of the feasibility study

Articles in the KW Record Waterloo Chronicle and University Gazette The installation of the lsquoMinirsquo Green Roof at the entrance of City Hall fostered some interest by the public Interviews were conducted by reporters of the local newspapers to convey details of the endeavour A text copy of each Article is included in Appendix E

Green Roof Display boards Display boards describing the Cityrsquos undertaking in the feasibility study showing examples of Green Roof projects and the potential benefits has been a resident display at the Waterloo Public Library

Physical Model of a sample Demonstration Site Once sufficient design information was decided for the proposed demonstration site a physical model scaled at 196 (18rdquo=1rsquo-0rdquo) was created This model was intended to provide a visual representation of a Green Roof project to prospective partnerships It was also intended to provide a concept a typical Green Roof application on a building such as the Waterloo Public Library so that the public could gain a visual understanding of the concept

Conference Poster A poster was developed by the Region of Waterloo describing the benefits of Green Roofs in a Public Health context The poster was shared at the Ontario Public Health Associationrsquos annual conference in Windsor Ontario in November 2003 See Appendix G

Green Roof Display at GRCA Water Forum A poster display board as well as a sample of lsquointensiversquo Green Roof was showcased during a one day GRCA watershed forum event The event is intended to bring forth ideas and concepts that conserve or improve the environment and promote water conservation The display was available to over two hundred visitors from the event

60 GREEN ROOF COSTS

Page 24


Although Green Roofs can be applied to various roof slopes for the purposes of this section discussion will reflect application on flat roofs

There are four basic components related to the lsquomake-uprsquo of a Green Roof project cost 1 Removal of existing roofing (except new buildings) 2 Installation of waterproof membrane 3 Installation of Green Roof system 4 Irrigation

The city wide implementation plan costs reflect application of an extensive Green Roof system as detailed in the early sections of this report This cost has been estimated to be $15000 per square metre including the above indicated four basic components

For Waterloo extensive Green Roofs are more feasible than the intensive variety as such extensive roof systems lend themselves to retrofit opportunities as with the demonstration site The retrofit involves a structural assessment of the roof assembly This will set the allowable additional load capacity of the roof and dictate the type and extent of Green Roof system that can be applied There are two basic approaches to Green Roof application

10 A Green Roof system can be applied over the existing roofing or

20 A Green Roof can be applied on the original roof surface once the existing roofing material has been removed

Traditionally older flat roofs involved the use of a multi ply felt tar and ballast (gravel) type of cover Existing built-up roof covers can weigh between 4 to 10 psf removal of this material can dramatically increase the load capacity of the roof and hence allow for a more diverse design opportunity for the Green Roof system Current light weight Green Roof systems can weight between 9 and 15 psf under saturated conditions this allows it to be placed on existing roofs with little or no structural modifications

Advantages of existing roofing material removal when installing a Green Roof system

bull Offers a better opportunity to add an insulation layer bull Provides for an increased Green Roof load allowance hence increased Green Roof benefits (ie

SWM capacity plant diversity etc) bull Provides an opportunity to repair the underlying roof surface bull Maintains low profile at edge flashing

Disadvantages bull Increases time to complete Green Roof application bull Increased costs

Cost Comparison

Below is a cost comparison between Green Roofs and conventional roofs (includes existing roof removal ndash retrofit applications)

Cost of Green Roofs (Idealized for Waterloo) $15000m2 Cost of roofing membranes $7500m2

Page 25


Cost of built-up roofs $6000m2

Green Roofs can potentially extend the life expectancy of the underlying roof covers by a factor of 2 to 3 times

70 NEED FOR FURTHER STUDY AND RESEARCH

City and Consultant representatives participated in a Green Roofs Think tank held at Toronto City Hall in October 2003 The think tank was held in response to provide a vehicle for the continuation of research on the benefits applicability construction and environmental impact of Green Roofs in Ontario The think tank was hosted by CRESTech an organization to fund research for the advancement of existing technology or new innovations Proceedings of the CRESTech Think Tank are included in Appendix F

The resulting experience with industry representatives by way of CHESTech gives the general indication that considerable information gaps exist for North American Green Roof applications and how the industry will be regulated It is recommended that this feasibility study be updated on a regular basis as new information and guidelines are developed

80 INCORPORATION INTO CITY PLANNING AND ENGINEERING POLICY

A Green Roof proposal submitted for the purpose of seeking cost or assessment incentive would require approval from City Engineering and Planning as if it were considered a SWM facility Under the approval as with SWM facilities a Green Roof would be subject to consideration on an individual basis and would require all input parameters and design calculations in a lsquoGreen Roof Design Reportrsquo The Green Roof type extent location etc would be evaluated Since a Green Roof is an integral part of the roof structure the design must also meet OBC loading and fire considerations In the event that a Green Roof is accepted as an option to comply with development requirements the City should incorporate a policy that recognizes the SWM function capabilities and offer incentives such as application of an lsquoin lieursquo value to development charges Green Roofs provide a significant benefit to providing effective Storm water Management as discussed in Section 31 of this report namely

bull Reduced value of runoff with associated reduced streambank erosion bull Reduction in peak flowrates during a storm event bull Reduced pollutant loads to the receiving stream including temperature pollution bull Trapping of air-borne particles and associated pollutants

The installation of Green Roofs is also viewed as a ldquosource controlrdquo measure when categorized with all of the other types of measures (ie conveyance measures and end-of-pipe measures) At source SWM measures are typically the most desirable (and effective) means of pollution prevention since it controls the pollutants before they get in the conveyance systems (in open streams or pipes) where the impacts of pollution start to occur Green Roofs being in the group of source control measures available are one of the most desirable SWM measures

Given their benefits Green Roofs should be encouraged as a means of SWM given the ancillary benefits as well That is providing greenspace environmental habitat reduced heat island effects and energy efficiency

One of the concerns regarding traditional ldquoat sourcerdquo SWM measures is the inability to ensure that any facility on private property will remain as an effective SWM facility The benefit of a Green Roof in

Page 26


this regard is that considerable work is required to remove it and it is very visible Generally Green Roofs require little maintenance after establishment and can provide some assurance that the water quality and quantity functions remain operational The requirement for use of a Green Roof could be included in the site plan approval process or possibly in building permit process

Given the effectiveness of Green Roofs for SWM it is recommended that a credit be provided during a permitting process at a predetermined value This value must be derived by planning and development departments of the municipality upon further study In addition technical credit for their overall effectiveness can be provided to reduce overall SWM requirements for a site

81 Regional Growth Management

The Region of Waterloo is currently undergoing a comprehensive Regional Growth Management Strategy that is intended to outline principles for future development in the Waterloo region which includes the cities of Kitchener Waterloo Cambridge and the Townships of North Dumpfries Wellesley Wilmot and Woolwich The region is expected to experience significant population and employment growth in the coming decades Local authorities (regional and municipal) are involved in developing this strategy which will depend significantly on land use practices such as urban lsquoin-fillrsquo and other intensification avenues The City of Waterloo recently published itrsquos lsquoHeight and Densityrsquo report which also follows the principles of urban sprawl and related urban demands such as the lsquoAutomobile Culturersquo that are required to support development Urban development is seen as a positive and necessary component of community sustainability however intensified urban development will result in measurable environmental and social impacts

Increased intensification will result in an increase of impermeable land surfaces and will have a significant effect on storm water management function The increased building surfaces and built infrastructure will also increase the urban heat island effect and exacerbate local air quality An increased population will also impose higher demands on energy and result in further stressing natural resources Concentrated urbanization can also negatively impact the habitat of local wildlife and may result in the displacement of airborne aquatic and terrestrial species that normally serve to provide a balance in the environment Green space thus becomes intrinsically valuable in providing connectivity to nature not only for the technical environmental benefits but also to maintain social health An aerial perspective of almost any highly urbanized city clearly demonstrates the need to find alternatives to an ever increasing demand on providing green space

Green Roof technology offers a viable avenue to mitigate the demands of urban development Green space policy can be developed to encourage use of Green Roofs to essentially provide best practices in compensating for the negative environmental impacts of development The following is a list of some environmental benefits offered by green space bull Storm water quantity attenuation infiltration flood attenuation water quality improvements bull Improvement of air quality and oxygen bull Social connectivity of natural surfaces and viewscapes bull Habitat for airborne and terrestrial species bull Mitigation of air and water runoff temperatures

These benefits can be considered similar to those offered by Green Roofs however to varying extents Current development controls do include provisions to mitigate some storm water impacts though very little exists to mitigate loss of habitat and potential degradation of air quality

Page 27


There is currently a policy by DFO (Department of Fisheries) that requires any development impacting a creek or fishery resource to compensate for loss of fish habitat This is called HADD (harmful alteration and destruction of fish habitat) If it is determined that the development is impacting a fishery resource the proponent must compensate for the loss of habitat by 2 to 3 times the calculated area of impact that is if 10 square metres of habitat is destroyed it must be replaced by 20 to 30 square metres of useful habitat elsewhere in the system

Similarly policies exist within the United States where if wetland areas are removed other wetlands must be created as a replacement Both of these policies indicate a move toward the preservation of environmental areas

If a similar policy can be applied to loss of green space the proponent would be made to compensate for the loss by using alternative methods that must essentially provide equal or at least a portion of the quantified benefits of the destroyed green space The best suited alternative method of compensating for green space within the area of development would be with the use of Green Roof technology This would encourage following a path toward responsible development It can be recommended that the Green Roof Feasibility Steering Committee participate to integrate a workable strategy for the City of Waterloo and for the Region of Waterloo This effort could coincide with the Regional Growth Management Strategy and provincial authorities working on the Smart Growth movement in Ontario to create through meaningful policy the mechanisms and incentives to encourage widespread adoption of Green Roof technology

82 Green Roof Design Guidelines

How does a prospective owner know how to design a Green Roof The requirement for mainstream implementation is needed for development of lsquoGreen Roofrsquo design guidelines Guidelines would vary from City to City depending on environmental targets ie pollution vs water quality Guidelines need to outline Green Roof targets and provide modelling parameters based on manufacturerrsquos values or growing medium depth composition and planting types (calculated values) Until guidelines are developed Green Roof proposals need to be evaluated on an independent basis

Page 28


90 DEMONSTRATION SITE SELECTION

91 Introduction

General

The process for the selection of a demonstration site focussed on selecting a building that not only optimised the potential Green Roof benefits but also served as a suitable demonstration site The term lsquodemonstrationrsquo implies that the building needed to be accessible for public viewing such that the Green Roof attributes could be showcased in order to provide a realistic impression of what Green Roofs represent for Waterloo During the later stages of the study development the future of the selected demonstration site building became undetermined The Library Task Force had begun reviewing operations and potential relocation was an option therefore the demonstration site at Albert St was delayed until the task force recommendations are approved by Council Further investigation is ongoing to select an alternative city owned building site for a green roof application This section of the report summarizes the process that was undertaken in selection of the initial demonstration site devising a Green Roof design developing an implementation plan and identification of possible alternative Green Roof Demonstration Sites

92 Municipal Building Selection for Green Roof Application

921 Municipal Building Inventory and Evaluation

A list of potential City owned buildings was assembled for consideration Four constraints were developed to pre-screen the building evaluation list The Green Roof constraints were

bull Municipally owned facility - the building needs to be municipally owned bull Suitability for flat roof installation - the building roof configuration needs to be conducive to Green

Roof installation bull Location - the location needs to be in an area where maximum overall benefits can be realized the

closer to the uptown core was preferred bull Heritage ndash the building could not be designated as a heritage building Buildings were eliminated

from further evaluation if they did not meet all four of the constraints

992 Municipal Building Candidates

As a condition of the funding received for this project buildings to be evaluated must be owned by the City of Waterloo The following is a list of buildings currently owned by the City of Waterloo

bull 155 Herbert Street bull 157 Herbert Street bull 159 Herbert Street bull City Hall ndash 100 Regina Street South bull Parkade ndash Willis Way bull Adult Recreation Centre ndash Caroline Street bull Library ndash Albert Street (potential future change of city owned status) bull Waterloo Memorial Recreation Complex ndash Father David Bauer Drive bull Fire Hall ndash Station 2 bull Waterloo Park Operations Building and Lions Lagoon bull RIM Park ndash Cart Storage Building ndash not yet built

Page 29


bull Service Centre bull Train Station bull Button Factory (Waterloo Community Arts Centre) bull Albert McCormick Community Centre bull Canadian Clay and Glass Gallery bull Cemeteries (Parkview) bull Manulife Financial Soccer amp Sports Centre bull Rink in the Park bull Moses Springer Community Centre (Arena) bull Waterloo Fire Department Headquarters bull Waterloo Fire Department Station 3 bull Wing 404 RCAFA Rotary Adult Centre

All eligible buildings meeting were carried forward for further evaluation see Appendix H

923 Building Categories- Municipal Building Selection Factors

Suitable for Flat Roof Installation Flat roofs are not essential for Green Roof installation however flat roof installations provide for increased opportunity with respect to vegetation types and roof access) For a demonstration site it was determined that the potential for access to the roof as well as the potential for various types of vegetation was an important consideration Based on this reasoning only buildings with flat roofs were carried forward

Location (Closeness to Uptown) Although there are benefits of Green Roofs no matter where they are located there are additional benefits for Green Roofs in the urban core of a City There is less green space in the urban core because green space wasnrsquot a focus during the early development of the core Due to space considerations there is limited if any opportunities for green space development Generally the urban core was developed without much regard for stormwater management and there is limited space available to implement measures Urban cores are generally easily accessible via transit Generally poor air quality and the urban heat island effect are more pronounced in urban cores than in subdivisions outside the City

For the purposes of evaluating the closeness to uptown the KingCaroline area was determined to be the urban core with building distances measured to this location Buildings within 1km of this area were determined to meet this constraint and were carried forward The building was to be included in the Uptown drainage area known as subwatersheds 319 320 amp 319

Heritage Site Addition of a Green Roof would alter the appearance and function of a building which would impact the heritage of the building For heritage sites it is very important to maintain the current appearance of the building therefore any buildings designated as heritage sites were eliminated from further evaluation

924 Suitable Buildings for Green Roof Installation - Scoped Building Sites

The following five buildings passed the preliminary site screening process and were subjected to an additional more detailed evaluation process

Page 30


bull City Hall ndash 100 Regina Street South bull Parkade ndash Willis Way bull Adult Recreation Centre ndash Caroline Street bull Library ndash Albert Street (potential future change of city owned status) bull Waterloo Park Operations Building and Lions Lagoon

925 Evaluation Matrix

The evaluation matrix was used as a method to identify a demonstration site location as well as to list other buildings in order of priority that may be eligible for a Green Roof installation A weighting system developed by the steering committee was used to rate each building

During the course of the study additional selection parameters arose and a different approach was taken for the final development of the City owned Building Green Roof plan This plan also identifies areas of the city that would be best benefited by Green Roofs beyond the City owned buildings in an effort to develop a City Wide Implementation Plan See Appendix I

100 DEMONSTRATION SITE

Based on the preliminary screening process five buildings were evaluated in further detail The criteria for evaluating the buildings were sorted into four categories function as a demonstration site structural cost and performance The criteria included

Function as a Demonstration Site bull Location (closeness to uptown) ndash maximum SWM benefits due to limited opportunity for other

SWM facilities and limited green space bull Building Aesthetics ndash overall architectural significance and adaptability to a Green Roof bull Accessibility to roof ndash ease of access for public viewing and maintenance bull Visibility of the site ndash potential viewscapes from travelled routes vantage points other buildings

etc bull Access to site ndash Availability of parking bus routes etc bull Suitability for multiple plots ndash to offer diversity in Green Roof types bull View from rooftop ndash possible attraction to view surroundings from roof bull Size of roof available ndash maximum roof size to maximize benefits

Structural bull Structural retrofit needs ndash roof construction design loads bull Ease of roof conversion ndash locationrelocation of existing HVAC units and access to the roof

Cost bull Cost of providing accessibility to Green Roof bull Ease of maintenance ndash providing equipment and access for maintenance bull Potential for roof replacement ndash does the existing roof need replacement

Performance bull Potential for improving energy efficiency ndash is the building in need of energy conservation

SWM benefit provided ndash does the building roof offer SWM benefits relative to the site

Page 31


101 Visibility and Function as a Demonstration Site

The buildings (City Hall Parkade Adult Recreational Centre Library and Lions Lagoon) were further evaluated based on their potential to function as a demonstration site They were visited to determine the location visibility of site building aesthetics accessibility to roof access to the site and view from rooftop A major focus of the study is to develop a demonstration site that people can easily access and that the Green Roof will be an enjoyable place to visit

Visibility of the site from a pedestrian perspective and surrounding area was determined by the Steering Committee to be important for a demonstration site The main visibility criteria included traffic circulation surrounding buildings that would draw visitors use of the building height of the roof from view points available parking destination significance and the demographic of users Virtual Green Roofs were added to each of the buildings demonstrate what the roofs might look like from a pedestrian perspective The library rated highest on the visibility criteria as well as the building aesthetics criteria

Although this category is largely subjective values were quantified wherever possible For example access to site was based on transit routes biking and walking paths

102 Initial Selected Demonstration Site Location

The Waterloo Public Library on Albert Street resulted in being the preferred location for a Green Roof demonstration site The library rated the highest in the evaluation matrix in the overall score As noted earlier the Library Task Force is currently investigating opportunities and options for library operations Thus the Albert Street building use as demonstration site was ultimately postponed until the task force recommendations have been approved by Council The library still offers many benefits for the implementation of a green roof and should be further considered in the future Buildings were rated on a 1-5 scale with 5 being the highest or most desirable rating The results of the evaluation matrix are presented in Appendix I

The Waterloo Public Library location was presented at the July 16 2003 Steering Committee meeting and meeting members voted and agreed that the library was the preferred location for the following reasons

bull Held potential to provide optimal environmental benefits offered by a Green Roof in itrsquos location

bull Was a candidate for imminent roof replacement bull Is a place of learning an optimal location to showcase new technologies bull Roof structure needed no structural reinforcement bull Varying roof levels offered diversity potential in Green Roof types bull Location of building is within other nearby attractions (Glass and Clay Silver Lake Marsland

Centre Waterloo Square Research Building) bull Lower roof level allowed facilitated public access potential bull Library currently boasts high rate of public circulation

Page 32


103 Initial Demonstration Site Design Development

Despite the exclusion of the library building from the demonstration site opportunities at this time the following sections have been retained in this report to outline the methods by which other future demonstration sites opportunities can be evaluated These include design factors that become essential in developing a feasible alternative bull Encourage a collective design opportunity that distils distinct perceptions of what should be

included such as lsquoDesign Charettersquo bull Provide a Green Roof Design Plan that incorporates the objectives bull Technical considerations such as loading and Green Roof types bull Access and social considerations

1031 Green Roof Design - Design Charette

The Design Charette took place on July 31 2003 at the Waterloo Public Library The purpose of the Charette was to brainstorm ideas for the design of various Green Roof components and access to the roof Two sketches of the library with Green Roof details and access were generated Subsequent to the meeting the best components of the two sketches were combined into a single preliminary design of the Green Roof for the Waterloo Public Library

1032 Green Roof Design Plan

The initial Green Roof design was a combination of concepts brought forward through the design Charrette The design was to follow the results received from the public survey as to what was perceived as important in a demonstration site

1 Air Quality 2 Energy Consumption 3 Water quality 4 Recreation bull Understanding of Technology bull Easy Access bull Pleasant to visit bull Variety of gardens bull proximity to uptown core

The direction given to the steering committee at the charette include the requirement for consideration of Social interests Technical and Access components

1034 Technical Considerations

The above plan view illustration of the library roof shows the results of the design charette noting the variation in planting types and access locations

Potential roof types were to be based on natural ecosystems and would be in conjunction with general city of waterloo practices and guidelines for vegetative species

Page 33


bull Grasses Alvar meadow bull Shrubs low growing - successional forest edge

alternate roof types could be possible given the variation in roof levels (intensive amp extensive) Performance of potential Green Roof in energy and swm pollution etc were to be considered when choosing Green Roof types

1035 Social interest Considerations

The design was to be conductive to integrating with current and future library activities

bull library activities - readingviewing area bull agricultural potential on roof

The function of the Green Roof is to be used to develop a public understanding of the technology and the corresponding environmental social and economic benefits bull Use - Learn study teach bull Can be seen from Albert Dupont amp Caroline streets bull Adjacent buildings Marsland United Church C2G2 amp Perimeter Institute

1036 Access Considerations

Types of Access Visual and Physical

Visual Access

bull Windows could be provided to view Green Roof with possible incorporation of mirrors to enhance view opportunities

bull View Ports could be created in walls to view Green Roof areas however may prove difficult since limited space is available

bull Illustrations and interpretive signage with discussion of the technology could be displayed within the library to convey the concepts

bull Photographs could be displayed of the Green Roof bull Representative Models could be displayed with an actual scaled representation of the

implemented Green Roof

Physical Access

Implementation of physical access was discussed as a component that could be phased over time as funding would permit The steering committee was asked to develop concepts for initial and ultimate access options

bull Access to one roof level was discussed with possibility to traverse between roof levels to gain addition vantage points Possible access points were identified

bull Existing access is a hatch at the roof of the maintenance room and is reached by a ladder The access to the maintenance room is also inconvenient Possibilities also existed involving the modification of the maintenance room by installation of a doorway onto the adjacent roof

bull Exterior Stairs from service entrance off Albert street parking lot was also discussed The stairway could be run parallel to the side of the building since only one story needed to be overcome This stairway would either be used as primary or secondary access depending on viability of other options by public and maintenance crews

Page 34


Barrier Free Access Options were discussed

bull Options included Exterior Ramps to the roof at the one story area of the building spatial constraints imposed difficulties in providing such a ramp

bull Exterior chair lifts or elevators were also considered as well as Interior elevators or modifications to the existing elevator

bull Modifications to stair well from Dupont parking lot was also discussed as a possibility

104 Sample Demonstration Site Assessment (Waterloo Public Library)

1041 Condition of Existing Roof

Several visits were made to view the library roof each giving an opportunity to view the condition of the existing roof surface after various rain events The following observations were noted

bull Ponding water throughout roof surface the older building demonstrated more severe ponding

bull Irregular surface undulations in the ballast and membrane

bull Areas of little to no ballast bull Sporadic cracking of bitumen were noted

1042 Structural Assessment

A structural assessment was undertaken for the Waterloo Public Library using the design drawings for the original building in 1967 and for the addition in 1987 In general the roof structure consists of a combination of concrete core slab panels on steel beams and purlins with a portion of the roof of concrete on corrugated steel roofing resting on open web steel joists The supporting structural components consists of concrete and steel columns throughout Since the roof structure is primary composed of precast concrete core slab a structural assessment of the slab could not be made since the reinforcing is unknown Attempts were made to retrieve information on the core slab from the original architects and the manufacturer however neither source was useful

The assessment approach was to proceed using the loading that was indicated for each roof section on the design drawings Working from these load values given the building code load calculation methods for the year in which the building sections were designed an updated load calculation was done using the current building code The current building code outlines a distinct loading calculation process from that of older codes Current climatological data for roof load estimations in present day is more accurate than was available in earlier years This essentially results in the live load values being slightly less that once perceived thus allowing room for other loads

A loading diagram was prepared to outline the possible additional loads that could be safely imposed using the existing roof structure without any structural reinforcement Depending on the location on the roof additional loads ranging from 12 to 40 psf (pounds per square foot) could be allowed This

Standing water on roof of Waterloo Public Library demonstrates current drainage issues and varying surface deficiencies

Page 35


additional loading restriction then set the limit for the Green Roof weight Although certain portions of the roof could withstand significantly greater loading than 12 psf the lower part of the range was to be used throughout and thus dictated that the lsquoextensiversquo Green Roof approach must be taken

Further analysis showed that removal of the existing roofing would also increase the overall additional load allowance providing further potential for Green Roof types

The structural analysis as well as the final roof loading diagram is included in Appendix C

1043 Roof Drainage Plan

An existing roof drainage plan was created based on a level survey of the roof surface Elevations were recorded around the perimeter of the building at each existing roof drain and at ponded water areas This plan was forwarded to Xeroflor in order for them to incorporate the drain locations with their Green Roof design The elevations revealed that certain areas of the roof did not have positive drainage to the roof drains and that ponded water varied in depth from 001 metres to 007 metres See Appendix C

105 Functional Final Design

During the development of the demonstration site design a small lsquominirsquo Green Roof was installed on the entrance of the Waterloo City Hall building (approx 10 square metres) The roof material was supplied by Xeroflor

1051 Xeroflor

Xeroflor is a Green Roof supplier based in Germany that has been designing and providing Green Roof technology know-how and materials to the industry for over thirty years As a result of the work done on City Hall a relationshippartnership was formed with Xeroflor whereby they would donate Green Roof material design expertise and direction for the design and proposed implementation of the demonstration site building Xeroflor required some technical information such as load and drainage details in order to proceed with their contribution See Appendix J

An analysis of the additional load capacity for the roof revealed that the Green Roof needed to be of a light weight type or lsquoextensiversquo variety This load restriction would potentially impose some limitation to the extent of vegetative diversity that was desired A loading diagram was provided to Xeroflor so that they could move forward on supplying a product that would meet the loading restrictions Throughout the process discussions with Xeroflor suggested that they would be able to provide alternative vegetative species to work towards the idealized design that had been developed while still maintaining a light weight system This would fall well within the load parameters of the roof

An updated Green Roof concept was developed for the library and was shown to the steering committee This concept was to be in keeping with the original concept however with simplified access and circulation locations The access was now to be located primarily at the existing service entrance by way of exterior stairs with a circulation path extending from the stairs along side the penthouse wall and towards the back of the building facing the rear parking lot This path would widen to accommodate seating areas and specimen trees and would provide an optimised vantage point to view the adjacent scenic areas such as silver lake Glass and Clay gallery etc At this area of the roof the following items were to provided bull Optimal views of adjacent areas

Page 36


bull Green Roof interpretive signage bull Views of Green Roofs bull Public seating bull Specimen tress (roof garden items) bull Art displays

The extents of the public access would be bounded by railing both to provide a safety barrier at the roof perimeter and also to protect the Green Roof from damage

Aerial view of existing roof of the Waterloo Public Library perspective visible from the Marsland Centre

Virtual rendition of proposed Green Roof application on the Waterloo Public Library proposed demonstration site

1052 Physical Model of the Initial Demonstration Site

Once sufficient design information was decided for the initial demonstration site a physical model scaled at 196 (18rdquo=1rsquo-0rdquo) was created This model was intended to provide a visual representation of the Green Roof project to prospective partnerships It was also intended to provide a concept of the green roof so that public unable to gain access to the roof can gain a sense of the project This concept was conceived during the design charette process as an option for an initial phase barrier free visual access

Side view of Model (Dupont St Perspective) Front view of Model (Albert St Perspective)

Page 37


1053 Xeroflor Extensive Roof System

The Xeroflor lsquoextensiversquo Green Roof system consists of bull Root Barrier bull Drainage layer bull Growing Medium bull Vegetation This system has the following characteristics bull Storm water retention capacity 37 litresm2 bull Air pollution removal potential 02 Kg per m2 per year bull Energy conservation lsquoRrsquo value 5 (est) bull Temperature Absorption up to 18degC degrees (compared to gravel roofs) bull Saturated Weight 9 to 12 psf

1054 Performance Characteristics of the Xeroflor Green Roof

The Surface area of the library roof to have been covered by Green Roof is approximately 1500 square metres This area is representative of the maximum area that could have been covered by Green Roof without interference of HVAC systems existing conduits and piping skylights and buffers to maintained adjacent to windows This amount of Green Roof that was to be provided for the initial demonstration site may be applied to alternative sites pending cooperation of Xeroflor and other technical considerations

Storm Water Management

The Xeroflor system contains a space layer beneath the growing medium that has the capability if storing 37 litres per square meter of Green Roof coverage This would have resulted in an overall storage capacity of approximately 52 cubic metres

Secondary Treatment of Runoff - Cistern Cisterns can be used to store rainwater temporarily as a method of SWM The overall plan for the demonstration included the use of a cistern as a method of secondary storm water treatment The cistern will provide addition storage capacity as well as sediment control The cistern was planned as phased addition to the building Initially the irrigation system for the Green Roof would be connected to the buildingrsquos water supply As phasing becomes financed and the cistern can be constructed the water supply for the roof irrigation system can be provided from the storage available in the cistern This can be applied in any demonstration site alternative pending availability of space

Heat Island The temperature of the Green Roof can be up to 40 degrees F (20degC) cooler that a comparative gravel surface roof Typically the surface of the Green Roof is similar to the air temperature above it thus reducing the potential of an air temperature increase

Energy A specific energy analysis was done using the Xeroflor Green Roof system For the given roof coverage an expected cost savings (in todayrsquos dollar) would have been approximately $45000 per year Additional savings would be realized if the insulation layer would be increased This is based on approximately 1500 to 1600 square metres of Green Roof coverage similar two to three story building types and sizes with similar coverage will result in comparative savings

Page 38


Air Pollution The air pollution can be calculated to be improved by approximately 280 kg of particulate per year

Extension of Roof Life The addition of the Green Roof is expected to extend the life of the underlying membrane by 25 years

Green Space The value of green space is outlined in the lsquoSample Implementationrsquo Appendix of this report

Aesthetic Value and Connectivity to Nature The aesthetic value as well as the connectivity to airborne species is difficult to quantify Amid the very evident extent of grey coloured impervious surface in the area as visible from the Marsland Centre the addition of the Green Roof would be a much improved visual perspective for the public as well as being a much more habitable area for birds and other species The economic or social value of such an amenity may never be quantified however given the proximity to adjacent buildings in the area from which interest may be fostered the Green Roof would have been located at an optimal location

1055 Cost Estimate

The primary cost components involved in implementing the initial demonstration site Green Roof include the following bull Access bull Existing roof removal bull Waterproofing bull Green Roof system installation bull Irrigation

Component costs were based on current labour and material costs A detailed cost estimate is included in Appendix K

105 Implementation Plan

The Implementation Plan provides information supporting the development of a program (justification) for the implementation of an example Green Roof demonstration site A sample Implementation Plan is included in Appendix N

The details regarding the benefits on Green Roofs are provided in the main body of this report

106 Alternative Green Roof Building site and Demonstration Site

The evaluation matrix was used as a method to identify a demonstration site location as well as to list other buildings in order of priority that may be eligible for a Green Roof installation

During the course of the study additional selection parameters arose and a different approach was taken for the final development of the City owned Building Green Roof plan The City Hall building ranked second priority for a site that would best benefit from a Green Roof after the initial library site thus the most suitable building for an alternative Green Roof application is the Waterloo City Hall Building It should be noted however that the City Hall building is not intended to serve as a Green Roof Demonstration site primarily since public access would be difficult and also due to the load restrictions on the roof assembly

Page 39


Demonstration Site

It remains a recommendation of this report that a library building is best suited for a demonstration site (pending a suitable location) for the same social reasons the initial demonstration site was selected At such time the library task force recommendations are approved by Council Either a new facility or the existing one at Albert St should be considered for a Green Roof application In a new building scenario loading should be considered along with an integrated design of environmental components with other building functions and architecture For a new building it is possible to showcase a variety of Green Roof types Intensive and Extensive using a variety of vegetation types

110 CITY HALL GREEN ROOF

Based on the initial demonstration site selection the following are primary factors involved in selecting the City Hall building as an alternative site


Cost bull Cost of installing a green roof bull Ease of maintenance ndash providing equipment and access for maintenance bull Potential for roof replacement ndash does the existing roof need replacement



111 Planning


A green Roof design plan needs to be created to outline the extents location and type of Green roof to be applied Given the structural constrains of the roof assembly the diversity of Green Roof type will be limited The drawings will be used to provide a guide for the installation as well as a tool for future Green Roof applications Drawings will include the following

bull Scale plan of roof bull Delineation of Green Roof limits bull Location of maintenance circulation pathways bull Location and details of irrigation system bull Cross section details of each Green Roof type bull Edging details bull Roof membrane details bull Drainage details bull Insulation details bull Flashing details bull Location and treatment of all roof protrusions including HCAV units

Page 40



A preliminary site visit was made to view the City Hall roof and make an assessment of the condition of the existing roof surface The following observations were noted

bull Pockets of ponding water exist throughout roof surface condensation from the HVAC units was observed to add to water ponding during summer months

bull Mildly irregular surface undulations in the ballast and membrane bull Areas of little to no ballast ballast appeared to be deteriorated bull Sporadic areas of cracked bitumen coating were noted


A preliminary structural assessment was undertaken for the City Hall roof during the building inventory portion of the Feasibility study At that time it was determined that the roof would not be able to sustain loading from an lsquoIntensiversquo type Green Roof system (representing 6rdquo of medium) Further investigation of Green Roof possibilities suggested that most retrofit Green Roof applications on existing city owned buildings would be able to provide support for an lsquoextensiversquo Green Roof system including the City Hall building

The assessment approach would include an assembly of lsquoAs Constructedrsquo or design drawings for the building in order to identify the supporting roof structure (ie beams columns purlins and roof sheathing

A loading diagram needs to be prepared to delineate the possible additional loads that could be safely imposed using the existing roof structure without any structural reinforcement This additional loading restriction then would set the limit for the Green Roof weight

In order to provide an adequate load capacity it will be necessary to remove the existing lsquobuilt-uprsquo roofing material


A roof drainage plan needs to be detailed to delineate surface drainage This needs to be done to verify that the existing roof drainage system will be adequate for accommodating the volumes resulting from the Green Roof A drainage plan will need to be forwarded to Xeroflor for verification of adequacy

VIEW OF EXISTING CITY HALL ROOF VIRTUAL IMAGE OF CIT

Page 41


The Surface area of the City Hall roof to be covered by green roof is approximately 1600 square metres This area is representative of the maximum area that would have been covered on the Waterloo Public Library The overall area of the City Hall roof is approximately 2500 square metres removing the areas occupied by the HVAC units and other obstructions it is anticipated that there is potential to cover the majority of the building with a Green Roof

112 Implementation Components

The primary cost components involved in implementing the green roof include the following

bull Existing roof removal bull Waterproofing bull Membrane protection bull Green roof system installation bull Irrigation

Existing roof removal

It is essential to remove the existing lsquobuilt-uprsquo roof in order to provide adequate load capacity for the Green Roof The existing roofing is in poor condition and should be replaced The removal will also require the reconfiguration of existing parapet wall flashing and connection to roof protrusions

Waterproofing

A new waterproofing membrane should be installed it is suggested to install an EPDM type membrane or similar

Membrane protection

A membrane protection layer should be installed over the new roofing membrane This layer protects the membrane during installation of the Green Roof system and provides an extra level of leak protection

Green Roof System

A lsquoXeroflorrsquo Green Roof system to the extend of approximately 1600 square metres should be installed over the membrane protection layer This is a light weight system of root barriers drainage layers growing mediums and low maintenance vegetation The installation can be done by City Staff at the direction of Xeroflor staff and other partners

Irrigation

An irrigation system should be installed in conjunction with the Green Roof This system has been developed by Xeroflor specifically for Green Roof installations and is necessary to ensure the success of the planting

Page 42


120 Study Recommendations







Page 43

REFERENCES amp SOURCE PAGE

City of Toronto Wet Weather Flow Program (March 2002) List of CSOStormwater Control Alternatives helliphelliphelliphelliphelliphelliphellip8 amp 9

Grand River Conservation Authority (1993) Laurel Creek Watershed Study helliphelliphelliphelliphelliphelliphellip10 11 amp 12

Canadian Geographic (May-June 2000) Blowinrsquo in the wind from (wwwcanadiangeographiccaMagazineMj00smogasp) helliphelliphelliphelliphelliphelliphellip13

Ontario Government (2001) Air Quality in Ontario 2001 Report helliphelliphelliphelliphelliphelliphellip13

Green Roofs for Healthy Cities (httpgreenroofsorgindexphppage=publicbenefits) helliphelliphelliphelliphelliphelliphellip13

Environment Canada Annual Heating Degree Days from (httpwwwclimateweatherofficeecgccaclimate_normalsresults_ehtml Province=ONT20ampStationName=ampSearchType=ampLocateBy=Provinceamp Proximity=25ampProximityFrom=CityampStationNumber=ampIDType=MSCampCity Name=ampParkName=ampLatitudeDegrees=ampLatitudeMinutes=ampLongitudeDegrees =ampLongitudeMinutes=ampNormalsClass=AampSelNormals=ampStnId=4832ampamplang= ENGamppageid=2) helliphelliphelliphelliphelliphelliphellip14

Gomez F amp Reig A (1998) Vegetation and Climatic Changes in a City Ecological Engineering Volume 10 Pages 355-360 helliphelliphelliphelliphelliphelliphellip15

The Greenroof Industry Resource Portal Life Expectancy of a Greenroof (wwwgreenroofscomeconomichtm) helliphelliphelliphelliphelliphelliphellip17

Robert Herman Green Roofs in Germany Yesterday Today and Tomorrow helliphelliphelliphelliphelliphelliphellip20 amp 21

Steven Peck and Ireen Wieditz Key Steps to Developing Local Green Roof Infrastructure Roof Markets helliphelliphelliphelliphelliphelliphellip20 amp 21

Benjamin Taube City of Atlanta Greenroof Demonstration Project helliphelliphelliphelliphelliphelliphellip20 amp 21

Cheney C amp Dr Rosenzweig C Green Roofs and Environmental Restoration Towards and Ecological Infrastructure for New York City helliphelliphelliphelliphelliphelliphellip20 amp 21 Lindhqvist V Institute and Augustenborgrsquos Botanical Roof Garden Swedish Green roof Initiative The Green Roof Society The International Green Roof helliphelliphelliphelliphelliphelliphellip20 amp 21

A

Jon Andereck K The Evolving Environmental Marketplace Using ldquoGreenrdquo to make ldquoGreenrdquo helliphelliphelliphelliphelliphelliphellip20 amp 21

LITERATURE REVIEW

Proceedings from Green Rooftops for Sustainable Communities Chicago May 29-30 2003

Stephen Peck and Monica Kuhn BES BArch OAA Design Guidelines for Green Roofs

CMHC SCHL (1999) Research Report ndash Green backs from Green Roofs

CMHC-SCHL Innovative Buildings ndash Merchandise Lofts Building green Roof Case Study Toronto Ontario

CMHC-SCHL Innovative Buildings ndash Fairmont Waterfront Hotel Green Roof Herb Garden Case Study Vancouver British Columbia

CMHC-SCHL Innovative Buildings ndash Waterfall Building Green Roof Case Study Vancouver British Columbia

The Green Roof Infrastructure Monitor from Green Roofs for Healthy Cities Volume 4 No 2 2002



Proceedings from the Waterloo Green Roof Infrastructure Workshop April 9th 2003

Cazenavette Herrick S A Garden on Your Roof

Minnesota Small Sites BMP Manual Impervious Surface Reduction ndash green Rooftops City of Toronto and Toronto Region Conservation Authority (November 2002) Eastview Community Centre and York University Rooftop Gardens Monitoring and Analysis Workplans

B

WEBSITES

wwwpeckcagrhccabouthtm wwwpeckcagrhccpublichtm wwwstormwatercenternetPollution_Prevention_Factsheetsgreen-rooftopshtml wwwroofmeadowcombenefitshtml wwwroofmeadowcomproductshtml wwwmagcocomextensive_intensivehtml wwwstormwatercenternetManual_BuilderCreditsSITEgreen20rooftopshtm wwwenncomnewsenn-stories20001212302000rooftops_40979 wwwgreenroofcomecologicalhtm wwwgreenroofcomeconomichtm wwwgreenfoofcomcomparisonhtm wwwlid-stormwaternetgreenroofsgreenroofs_benefitshtm wwwgreenroofsystemsorkyorkstatusfinalsentrhtm wwwgreenroofscagrhccoverviewdemohtm httpoeenrcangccanewbuildingscbipcfm wwwxerofloracom wwwlid-stormwaternetgreenroofsgreenroofs_specshtm wwwatmospherempgdeenidgxhtm

FIGURE REFERENCES

Page 4 Chicago City Hall wwwaslaorgmeetingsawardsawds02chicagocit hallhtml

Page 5wwwxerofloracom

C

Page 6 wwwxerofloracom

Page 6 Source American Wick Drain Corp


19

4 49


21

D

Page 14 Source Model National Energy Code for buildings (MNECB) for Ontario Region A

7

Page 14 Source Heat Island Group

Page 15 Source xerofloracom


E


CITY OF WATERLOO GREEN ROOFS FEASIBILITY STUDY And City Wide Implementation Plan

TABLE OF CONTENTS

EXECUTIVE SUMMARY i

ACKNOWLEDGEMENTS vi

10 INTRODUCTION 4

11 GENERAL 4 12 STUDY OBJECTIVE 5

20 GREEN ROOF DEFINITION 5

30 FEASIBILITY APPROACH 7

POTENTIAL GREEN ROOF BENEFITS 7 Primary Benefits7 Secondary Benefits7

31 STORM WATER MANAGEMENT 7 311 Common methods of controlling the storm water effects of new development 8 312 Common methods of controlling the effects of existing development 9 313 Potential water quality improvements in City Watercourses10 314 Flooding11

32 AIR POLLUTION REDUCTION 12 33 ENERGY EFFICIENCY 13 34 URBAN HEAT ISLAND 15 35 GREEN SPACE 15 36 CONNECTIVITY TO AIRBORNE SPECIES (HABITAT) 16 37 EXTENSION OF ROOF LIFE SPAN 16 38 URBAN AGRICULTURE 17

40 CITY WIDE IMPLEMENTATION PLAN 17

41 CITY WIDE PROGRAM 19 42 PROGRAMS IN OTHER AREAS 20 43 COSTS AND BENEFITS 21 44 POTENTIAL PARTNERS 23

50 PUBLIC INVOLVEMENT 23

Public Outreach 23 Articles in the KW Record Waterloo Chronicle and University Gazette 24 Green Roof Display boards 24 Physical Model of a sample Demonstration Site 24 Conference Poster24 Green Roof Display at GRCA Water Forum24

60 GREEN ROOF COSTS 24

70 NEED FOR FURTHER STUDY AND RESEARCH 26

80 INCORPORATION INTO CITY PLANNING AND ENGINEERING POLICY 26

81 REGIONAL GROWTH MANAGEMENT 27

Page 1





















APPENDICES



Page 3


EXECUTIVE SUMMARY









i









ii




Public Involvement











iii













iv











v


ACKNOWLEDGEMENTS







Sincerely


vi


10 Introduction

11 General






Page 4




12 Study Objective










Page 5


species

Energy Usereduction



(SWM)





Reduced runoff

volumes


poor air related




Reduced loading on

hydro power

Reduced heat loss

Increased aesthetic

urbanscape


of insects


airborne


Reduced erosion in

creeks




In runoff


Reduced storm sewer

costs


materials

Reduction in creek

maintenance

Reduced heating and

cooling costs

Reduces costs of

future roof














Filter Cloth


Page 6





Primary Benefits


Secondary Benefits






Page 7











Page 8











Page 9










Page 10

Page 11




























Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E
















Page 2






APPENDICES




EXECUTIVE SUMMARY









i









ii




Public Involvement











iii













iv











v


ACKNOWLEDGEMENTS







Sincerely


vi


10 Introduction

11 General






Page 4




12 Study Objective










Page 5


species

Energy Usereduction



(SWM)





Reduced runoff

volumes


poor air related




Reduced loading on

hydro power

Reduced heat loss

Increased aesthetic

urbanscape


of insects


airborne


Reduced erosion in

creeks




In runoff


Reduced storm sewer

costs


materials

Reduction in creek

maintenance

Reduced heating and

cooling costs

Reduces costs of

future roof














Filter Cloth


Page 6





Primary Benefits


Secondary Benefits






Page 7











Page 8











Page 9










Page 10

Page 11




























Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E






APPENDICES



Page 3


EXECUTIVE SUMMARY









i









ii




Public Involvement











iii













iv











v


ACKNOWLEDGEMENTS







Sincerely


vi


10 Introduction

11 General









12 Study Objective










Page 5


species

Energy Usereduction



(SWM)





Reduced runoff

volumes


poor air related




Reduced loading on

hydro power

Reduced heat loss

Increased aesthetic

urbanscape


of insects


airborne


Reduced erosion in

creeks




In runoff


Reduced storm sewer

costs


materials

Reduction in creek

maintenance

Reduced heating and

cooling costs

Reduces costs of

future roof














Filter Cloth


Page 6





Primary Benefits


Secondary Benefits






Page 7











Page 8











Page 9










Page 10

Page 11




























Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E


EXECUTIVE SUMMARY









i









ii




Public Involvement











iii













iv











v


ACKNOWLEDGEMENTS







Sincerely


vi


10 Introduction

11 General






Page 4




12 Study Objective











species

Energy Usereduction



(SWM)





Reduced runoff

volumes


poor air related




Reduced loading on

hydro power

Reduced heat loss

Increased aesthetic

urbanscape


of insects


airborne


Reduced erosion in

creeks




In runoff


Reduced storm sewer

costs


materials

Reduction in creek

maintenance

Reduced heating and

cooling costs

Reduces costs of

future roof














Filter Cloth


Page 6





Primary Benefits


Secondary Benefits






Page 7











Page 8











Page 9










Page 10

Page 11




























Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E









ii




Public Involvement











iii













iv











v


ACKNOWLEDGEMENTS







Sincerely


vi


10 Introduction

11 General






Page 4




12 Study Objective










Page 5


species

Energy Usereduction



(SWM)





Reduced runoff

volumes


poor air related




Reduced loading on

hydro power

Reduced heat loss

Increased aesthetic

urbanscape


of insects


airborne


Reduced erosion in

creeks




In runoff


Reduced storm sewer

costs


materials

Reduction in creek

maintenance

Reduced heating and

cooling costs

Reduces costs of

future roof














Filter Cloth






Primary Benefits


Secondary Benefits






Page 7











Page 8











Page 9










Page 10

Page 11




























Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E




Public Involvement











iii













iv











v


ACKNOWLEDGEMENTS







Sincerely


vi


10 Introduction

11 General






Page 4




12 Study Objective










Page 5


species

Energy Usereduction



(SWM)





Reduced runoff

volumes


poor air related




Reduced loading on

hydro power

Reduced heat loss

Increased aesthetic

urbanscape


of insects


airborne


Reduced erosion in

creeks




In runoff


Reduced storm sewer

costs


materials

Reduction in creek

maintenance

Reduced heating and

cooling costs

Reduces costs of

future roof














Filter Cloth


Page 6





Primary Benefits


Secondary Benefits
















Page 8











Page 9










Page 10

Page 11




























Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E













iv











v


ACKNOWLEDGEMENTS







Sincerely


vi


10 Introduction

11 General






Page 4




12 Study Objective










Page 5


species

Energy Usereduction



(SWM)





Reduced runoff

volumes


poor air related




Reduced loading on

hydro power

Reduced heat loss

Increased aesthetic

urbanscape


of insects


airborne


Reduced erosion in

creeks




In runoff


Reduced storm sewer

costs


materials

Reduction in creek

maintenance

Reduced heating and

cooling costs

Reduces costs of

future roof














Filter Cloth


Page 6





Primary Benefits


Secondary Benefits






Page 7





















Page 9










Page 10

Page 11




























Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E











v


ACKNOWLEDGEMENTS







Sincerely


vi


10 Introduction

11 General






Page 4




12 Study Objective










Page 5


species

Energy Usereduction



(SWM)





Reduced runoff

volumes


poor air related




Reduced loading on

hydro power

Reduced heat loss

Increased aesthetic

urbanscape


of insects


airborne


Reduced erosion in

creeks




In runoff


Reduced storm sewer

costs


materials

Reduction in creek

maintenance

Reduced heating and

cooling costs

Reduces costs of

future roof














Filter Cloth


Page 6





Primary Benefits


Secondary Benefits






Page 7











Page 8




















Page 10

Page 11




























Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E


ACKNOWLEDGEMENTS







Sincerely


vi


10 Introduction

11 General






Page 4




12 Study Objective










Page 5


species

Energy Usereduction



(SWM)





Reduced runoff

volumes


poor air related




Reduced loading on

hydro power

Reduced heat loss

Increased aesthetic

urbanscape


of insects


airborne


Reduced erosion in

creeks




In runoff


Reduced storm sewer

costs


materials

Reduction in creek

maintenance

Reduced heating and

cooling costs

Reduces costs of

future roof














Filter Cloth


Page 6





Primary Benefits


Secondary Benefits






Page 7











Page 8











Page 9










Page 11




























Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E


10 Introduction

11 General






Page 4




12 Study Objective










Page 5


species

Energy Usereduction



(SWM)





Reduced runoff

volumes


poor air related




Reduced loading on

hydro power

Reduced heat loss

Increased aesthetic

urbanscape


of insects


airborne


Reduced erosion in

creeks




In runoff


Reduced storm sewer

costs


materials

Reduction in creek

maintenance

Reduced heating and

cooling costs

Reduces costs of

future roof














Filter Cloth


Page 6





Primary Benefits


Secondary Benefits






Page 7











Page 8











Page 9










Page 10




























Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E




12 Study Objective










Page 5


species

Energy Usereduction



(SWM)





Reduced runoff

volumes


poor air related




Reduced loading on

hydro power

Reduced heat loss

Increased aesthetic

urbanscape


of insects


airborne


Reduced erosion in

creeks




In runoff


Reduced storm sewer

costs


materials

Reduction in creek

maintenance

Reduced heating and

cooling costs

Reduces costs of

future roof














Filter Cloth


Page 6





Primary Benefits


Secondary Benefits






Page 7











Page 8











Page 9










Page 10

Page 11





































Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E


species

Energy Usereduction



(SWM)





Reduced runoff

volumes


poor air related




Reduced loading on

hydro power

Reduced heat loss

Increased aesthetic

urbanscape


of insects


airborne


Reduced erosion in

creeks




In runoff


Reduced storm sewer

costs


materials

Reduction in creek

maintenance

Reduced heating and

cooling costs

Reduces costs of

future roof














Filter Cloth


Page 6





Primary Benefits


Secondary Benefits






Page 7











Page 8











Page 9










Page 10

Page 11




























Page 12












For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E












Filter Cloth


Page 6





Primary Benefits


Secondary Benefits






Page 7











Page 8











Page 9










Page 10

Page 11




























Page 12










Page 13



For example







49

7

4

21

19








ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E





Primary Benefits


Secondary Benefits






Page 7











Page 8











Page 9










Page 10

Page 11




























Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space














sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E











Page 8











Page 9










Page 10

Page 11




























Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc















Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E











Page 9










Page 10

Page 11




























Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16















STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E










Page 10

Page 11




























Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000




NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E




























Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA























Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E












Page 12










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19






















Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E










Page 13



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20















bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E



For example







49

7

4

21

19







Page 14


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit













Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E


ERM

AL G

RAD

IEN

T



COOL (LOW TEMP)

chuxted










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2























60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E










35 Green Space




Page 15











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




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21

D


7




E











sewers etc


Page 16














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison















Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E














Page 17


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25





















Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E


STEP 1




STEP 2


STEP 3


STEP 4






Less than 10 psf




























2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26















Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E

















2007 2012 $16400000 $1800000(LOT)



2005-2006 $25000000 2800 $42000000


Page 18



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27









91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E



NA NA


2008 $38800000 4350 $65250000


NA NA 320 $4800000


NA NA NA NA











Page 19













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General






















Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E













Page 20










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29

























Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E










Page 21






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30


























Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E






bull SWM Benefit




bull Energy Benefit









Page 22





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31

























Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E





Difference $8758m2













Page 23











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32























Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E











60 GREEN ROOF COSTS

Page 24













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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D


7




E













Cost Comparison



Page 25













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

























1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E













Page 26









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor












Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




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D


7




E









Page 27







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36



















Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E







Page 28



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37
















1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E



91 Introduction

General












Page 29











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate










Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E











Page 30















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning

















Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




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21

D


7




E















Page 31












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40





















Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




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21

D


7




E












Page 32














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation










Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




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21

D


7




E














Page 33










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42






















A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




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D


7




E










Visual Access






Physical Access





Page 34

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




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D


7




E

















Page 35









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




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D


7




E









1051 Xeroflor




Page 36









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




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21

D


7




E









Page 37











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E











Page 38






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

4 49


21

D


7




E






1055 Cost Estimate









Page 39


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E


Demonstration Site








111 Planning




Page 40














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




19

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21

D


7




E














Page 41








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




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D


7




E








Waterproofing


Membrane protection


Green Roof System


Irrigation


Page 42









Page 43














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




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D


7




E









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A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




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D


7




E














A


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




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D


7




E


LITERATURE REVIEW













B

WEBSITES


FIGURE REFERENCES



C




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7




E

WEBSITES


FIGURE REFERENCES



C




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7




E

wwwxerofloracom



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E




E

Green Roofs Feasibility Study and City Wide Implementation Plan

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Transcript of Green Roofs Feasibility Study and City Wide Implementation Plan