Green Roof

1
Green Roof
CDAE 170
2
Whats been done?

• Green roofs in Iceland, 1800s
• Technology in Germany 1970s
• American Hydrotech Inc, American Wick Drain
  Corporation, etc.
• Toronto City Hall, 2000

3
Advantages

• Ecological
• Storm water control and treatment
• Reduce urban heating
• Filter airborne toxins
• Economic
• Natural Insulation
• Useful Space
• Aesthetic
• Psychological

4
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. Advantage
s 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.
5
Green Roof Construction
Intensive Soil Substrate Fleece Filter Fabric Screen Optima Perlite Drainage Layer Rainwater Retention Layer Insulation Layer Root Barrier Course Waterproof Membrane Protective Barrier

6
Agriculture and Bioproduction

• Apples, bananas, cherries, raspberries,
  blueberries, tomato, peppers, spices and herbs
• Flowers and decorative plants
• Native species to replant in surrounding areas

7
Conclusion

• Economic
• Ecological
• Aesthetic
• Physological Advantages
• Food production opportunity