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Green Roof. CDAE 170. What’s been done?. Green roofs in Iceland, 1800’s Technology in Germany 1970’s American Hydrotech Inc, American Wick Drain Corporation, etc. Toronto City Hall, 2000. Advantages. Ecological Storm water control and treatment Reduce urban heating
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Green Roof CDAE 170
What’s been done? • Green roofs in Iceland, 1800’s • Technology in Germany 1970’s • American Hydrotech Inc, American Wick Drain Corporation, etc. • Toronto City Hall, 2000
Advantages • Ecological • Storm water control and treatment • Reduce urban heating • Filter airborne toxins • Economic • Natural Insulation • Useful Space • Aesthetic • Psychological
Extensive verse Intensive Green Roof EXTENSIVE GREEN ROOF • Thin growing medium; little or no irrigation; stressful conditions for plants; low plant diversity. Advantages: • Lightweight. • Suitable for large areas. • Low maintenance • Often no need for irrigation • Often suitable for retrofit projects. • Can leave vegetation to grow spontaneously. • Relatively inexpensive. • Easier for planning authority to demand as a condition of planning approvals. Disadvantages: • Less energy efficiency and storm water retention benefits. • More limited choice of plants. • Usually no access for recreation or other uses. • Unattractive to some, especially in winter. INTENSIVE GREEN ROOF • Deep soil; irrigation system; more favorable conditions for plants; high plant diversity; often accessible. Advantages: • Greater diversity of plants and habitats. • Good insulation properties. • Can be made very attractive visually. • Often accessible, with more diverse utilization of the roof. i.e. for recreation, growing food, as open space. • More energy efficiency and storm water retention capability. Disadvantages: • Greater weight loading on roof. • Need for irrigation and drainage systems requiring energy, water, materials. • Higher capital & maintenance costs. • More complex systems and expertise.
Agriculture and Bioproduction • Apples, bananas, cherries, raspberries, blueberries, tomato, peppers, spices and herbs • Flowers and decorative plants • Native species to replant in surrounding areas
Conclusion • Economic • Ecological • Aesthetic • Physological Advantages • Food production opportunity