Post on 14-Dec-2015
A Retrofit Strategy for Aging Multi-unit Residential Buildings in Toronto
Marianne TouchieNovember 29th, 2012Passive House Canada AGM
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Outline
• Motivation for MURB energy retrofit research• Performance issues and the status quo• Current Research at the University of Toronto
including NTED™
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Motivation for MURB retrofit research
Source: CMHC, Tower Renewal Guidelines
Housing starts in the GTA
Housing Stock Residential GHG Emissions
30% 40%
Indoor Environmental Quality Issues:
Draughts and overheating
High relative humidity and mould growth
Transmission of smoke, odours, noise, insects
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Causes of performance issues
Minimal Thermal
Resistance
Uncontrolled Air Leakage
Thermal Bridge
through Slab
Image source: Tower Renewal Guidelines
Architectural
Causes of performance issues
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Operational + ++ +
+ ++ ++ ++ ++ ++ ++ +
Causes of performance issues
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OperationalNegative
Positive
Balanced
Dynamic pressures (wind, stack and
mechanical)
ArchitecturalLoose envelope and
interior partitions
+
=Uncontrolled
air flow
Overclad
Enclose balconies
Upgrade HVAC
controls
Install sensors
Replace MAU
Replace windows
Install solar thermal
Submeter
Replacelighting
Recaulk windows
Cost
Time Required for Implementation
Replace boiler
Install PVs
30%
Sources: Natural Resources Canada; Toronto Atmospheric Fund
Space HeatingRequirements
Typical Retrofit
Existing Building
Current Retrofit Strategies
IEQ issues remain
IEQ issues solved?
Emerging Techniques
Compartmentalization
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Reduced stack pressure results in less infiltration
Corridor ventilation remains insufficient
Source: CMHC 2005
Suite-based Equipment
Emerging Techniques
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Preferred by condo owners, building managers
In conjunction with a central system and without compartmentalization
Source: Finn Projects
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Proposed Solution: NTED™
18°C 0°C
Conduction and Air Leakage
Heat Transfer
Adiabatic and Airtight
-6°CEnclosedBalcony
Ventilation Air Heating
ExteriorApartment Heat Recovery
Zone
Combine emerging techniques with a modified version of Nested Thermal Envelope Design™ for single family homes
NTED™ Research ObjectivesDetermine the viability of NTED™ application in the MURB sector
Through monitoring, gather detailed information about MURB operation
Verify suite-level performance through laboratory testing
Develop model with energy simulation program
Image source: Tower Renewal Guidelines
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Monitoring Program
Building-level and suite-level monitoring
12-month period
35 Charles Street Student Family Residences
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Building-level: Natural gas (hourly) and electricity use (sub-hourly)
Suite-level: electricity use E
E
Monitoring Program
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ambient lighting sensors LL
D D
D
D
P
P
P
P
Monitoring Program
E
T/R
T/RSelected suites: pressure differential sensors P (at corridor, exterior, exhaust), displacement sensors D window),
Building-level: Natural gas (hourly) and electricity use (sub-hourly)
Suite-level: electricity use E temperature T relative humidity R
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Laboratory TestingClimate Simulator at the
University of Toronto
Enclosed Balcony
Warm Room
Cold Room
HP HRV
Apartment
Chill
er
Baffle
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Energy Modelling
Test various retrofit strategies Envelope Types
Base WallR2000 WallOptimized WallBase Wall + OvercladdingNew Wall + New Wall
In-Suite Mechanical componentsHeat Recovery Ventilator Heat Pump Domestic Hot Water Tank
Sensitivity AnalysesOrientationFenestration-to-wall ratioHRZ dimensionsEnvelope air tightnessEnvelope thermal resistance
Cooling season performance
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Laboratory ResultsRetrofit Strategies
for MURBs
Bringing it all together...
Building Monitoring
Laboratory Results
Energy Simulations
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References• Canadian Mortgage and Housing Corporation. 1997. Energy Audits of High-Rise Residential Buildings.
Technical Series 97-100. from http://www.cmhc-schl.gc.ca/publications/en/rhpr/tech/97100.htm
• Canada Mortgage and Housing Corporation. 2005. “Assessment of Suite Compartmentalization and Depressurization in New High-Rise Residential Buildings,” Technical Series 05-112.
• Dixon, E., Pressnail, K.D., Richman, R., Touchie, M. 2010. Thermal Performance of the Exterior Envelopes of Whole Buildings XI International Conference: NTED: An innovative design using nested thermal envelopes to achieve significant reductions in energy use.
• Finn Projects (Synchronicity Projects Inc.) 2003."Survey of In-Suite Space and Domestic Hot Water Heating Systems in Multi-unit Residential Buildings," Canada Mortgage and Housing Corporation Research Report.
• Kesik, T. and Saleff, I., 2009. Tower renewal guidelines. Toronto: University of Toronto.
• Natural Resources Canada. 2008. Comprehensive Energy Use Database Tables. [Online]. Available: http://oee.nrcan.gc.ca/corporate/statistics/neud/dpa/trends_res_on.cfm
• United Way. (2011) Vertical Poverty: Poverty by Postal Code 2. United Way Toronto.