Green Roofs in Chi Town

Alanna Evans, Jennifer Kramer, Anthony Burton

The Big PictureGlobal Warming

Overuse of Resources:DeforestationIntensive FarmingLand DegradationResource Depletion

Waste

Air, Soil, and Water Pollution

Waste Management

Pollution..

Road Map•What are Green Roofs?•Analyze roofs’ reduction in:

–urban heat island effect–pollutants in the air–rainfall runoff

•How would implementing Green Roofs affect a city like Chicago?

William McDonough

•Cradle to Cradle- Sustainability

•Implementation of Chicago

•City Hall design

(McDonough 2006)

What are Green Roofs?• Green Roofs-gardens grown on top of a home

with waterproofing membrane underneath

• 2 types:– Extensive-mosses and other shallow-root

plants; little maintenance– Intensive-larger vegetation planted in

deeper soil

(Wikipedia 2006)

Our Hypothesis:• Implementing McDonough’s green roof

design on homes throughout the city of Chicago will reduce the urban heat island effect, reduce rainfall runoff, and improve air quality within the city.

Urban heat island effect

•Urban centers-ave. temps of 6-10° F higher

•Air temp over green roof-90° F•Air temp over standard roof-

102° F•Result: Lower need for air

conditioning (Czarnecki 2003)

Our Model

Stella Model for Urban Island

• ((Number of Standard Roofs*102)+((100 – Number of Standard Roofs)*90))/100

• 2% annual transformation rate• 13.3% homes left as std.• 91.6° F after 100 yrs

Reduction of Rainfall Runoff

• Runoff-precipitation waters that flow into uncontrolled water bodies

• Standard roof- 9% caught • Green roofs- 55% caught• Result- reduction in flooding

risks; inc. in water quality of nearby water bodies

(Mentens 2006)

Air Quality

• 1 m2 green roof- reduction of 0.2kg/yr of air particulate

• If 10% convert to green roofs: 2.6x106kg of particulates removed

• Result: cleaner, more breathable air

(Ardron 2006)

Excel Graph for Particulate Reduction

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Air Particulate Reduction

Why Everyone Should Get OneReducedSummerTemps!!!

Improved water quality!!!

FewerFloods!!!

Less airPollution!!!

CitationsArdron, Keith. 2006. “Green Roof Benefits.”

<http://www.eltgreenroofs.com/greenroofs-benefits.html> (Oct 25, 2006).

Czarnecki, John E. 2003. “From the roof of city hall to rows of bungalows, Chicago goes green.” Architectural Record. 191 (2): 79-80.

McDonough, William and Michael Braungart. 2002. “The Living City : Nature, Design, and the Greening of Chicago .” <http://www.mcdonough.com/writings/living_city.htm#> (October 26, 2006).

Mentens, J., Raes D., and Hermy, M. 2006. “Green roofs as a tool for solving the rainwater runoff problem in the urbanized 21st century?” Landscape and Urban Planning. 77 (3): 217-226.