The Greening of the Rooftop

Module 2

Basic Principles of Green Design

The Greening of the Rooftop

Sustainable Design

• The art of designing the built environment in accordance with sustainable principles

• A growing force in:– architecture & landscape architecture– urban planning and development– engineering– Industrial & interior design

Source: Wikipedia (http://en.wikipedia.org/wiki/Sustainable_design)

The Greening of the Rooftop

Principles of Sustainable Design

1. Low Impact Materials

2. Energy Efficiency / Clean Energy

3. Quality & Durability

4. Reuse, Renewal, Recycling

5. Measurement & Assessment

6. Management Control

Source: Wikipedia (http://en.wikipedia.org/wiki/Sustainable_design#Principles_of_sustainable_design)

Green Design Principle #1

Low Impact Materials

Low Impact Materials

What are the Key Impacts?

Impact: (1)

Global Warming

Ozone Depletion

Photochemical Oxidants

Acidification

Eutrification

Human Health Toxicity

Eco-Toxicity

(1) From EPA Tool for the Reduction and Assessment of Chemical and other Environmental Impacts (TRACI), and as recommended by USGBC LEED LCA Working Group A, December, 2006

Caused By:

Greenhouse Gasses

Ozone Depleting Chemicals

Ozone Producing Chemicals

Acid Rain Gasses

Oxygen Depleters in Water

Long-Acting Toxic Chemicals

Long-Acting Pesticides & Herbicides

• Reduce Embodied Energy

• Eliminate Toxic Components

• Achieve Sustainable Production

• Eliminate Unnecessary Steps

• Design with the End in Mind

Low-Impact Materials

Low-Impact Design Strategies

Green Design Principle #2

Energy Efficiency / Clean Energy

• Produce Clean Energy– Solar / Geothermal / Wind / Biomass

• Reduce Embodied Energy– Raw Material Extraction / Manufacturing / Transportation

– Increase Durability / Recycling

• Reduce Operating Energy– Heating / Cooling / Lighting / Equipment

Energy Efficiency / Clean Energy

Global Energy Strategies

Why is Operating Energy So Important?

Operating Energy versus Embodied Energy

Operating energy accounts for over 85% of total energy usage in buildings

Source: US DOE 2006 Buildings Energy Data Book

O 10 20 30 40 50

80

70

60

50

40

30

20

10

0

En

erg

y (G

J/m

2)

Building Life (Years)

Operating Energy

Recurring Embodied Energy(Repair & Maintenance)

Total Energy

Initial Embodied Energy

Why is Operating Energy So Important?

Clean Energy versus Fossil-Fuel Energy

Global Energy Supply: 1980 – 2030 (2)

(Billions of Tons of Oil Equivalents)

Coal

Oil

Gas

Other (1)

BiomassHydroNuclear

(1) Solar, Wind, Geothermal(2) International Energy Agency “World Energy

Outlook, 2006” (Reference Scenario)

Reducing operating

energy will be the best

opportunity for many

years

Energy Efficiency / Clean Energy

Roofing Strategies

• Reduce peak energy demand with cool roofs (Module 6)

• Reduce total energy demand with increased roof insulation (Module 7)

• Generate clean rooftop energy using PV, daylighting, or wind (Module 8)

Green Design Principle #3

Quality & Durability

• Increase Quality– Improve function & value

• Improve Durability– Extend service life

Green Building Design

Quality & Durability

Increased Quality = Enhanced Function

Improved Durability = Expanded Life Cycle

• Enhance & Combine Functions– Multifunctional spaces– Multifunctional products & systems

• Anticipate Extreme Conditions– Storm (wind / rain / hail)– Traffic & abuse

Quality & Durability

Quality & Durability Strategies

More to follow in Module 7 - High Performance Roofs

Green Design Principle #4

Reuse, Renewal, Recycling

• Planned Reuse

• Planned Maintenance

• Planned Removal & Recycling

Green Building Design

Reuse, Renewal, Recycling

The Key is Planning

• Life Cycle Planning– When should maintenance & repair be anticipated?– What is the best combination of initial durability and periodic service?

• Design with the End in Mind– How can eventual removal be simplified?

Reuse, Renewal, Recycling

Strategies

More to follow in Module 7 - High Performance Roofs

Green Design Principle #5

Measurement & Assessment

• Quantify the Impacts / Benefits– Identify the impacts

– Measure the impacts

– Weigh and combine the impacts

• Assess the Impacts Over the Life Cycle – Compare alternatives

– Look for opportunities for continuous improvement

Green Building Design

Measurement & Assessment

Measurement & Assessment

The Measurement & Assessment Process:

Life Cycle Assessment(LCA)

More to follow in Module 3 - Life Cycle Assessment

Green Design Principle #6

Management Control

• Environmental Management System– A long-term, ongoing plan for managing environmental

impacts

• Project Commissioning– The starting point for long-term environmental management

Environmental Management Control

Key Elements

More to follow in Module 7 – High Performance Roofs

The Principles of Sustainable Design

Summary & Review

1. Low Impact Materials

2. Energy Efficiency / Clean Energy

3. Quality & Durability

4. Reuse, Renewal, Recycling

5. Measurement & Assessment

6. Management Control