A green roof can reduce water run-off by
50–90 %; any remaining water flows from the roof
with a delay. Outlets, pipes and drains can be
reduced in capacity, thereby saving construction
costs. Sewer costs can be reduced in some areas.
c.Increased Roofing Membrane Durability
The presence of a green roof decreases
the exposure of waterproofing membranes to large
temperature fluctuations, that can cause microtearing,
and ultraviolet radiation.
d.Fire Retardation
Green roofs have a much lower burning
heat load (the heat generated when a substance
burns) than do conventional roofs (Köehler 2004).
e.Urban Agriculture (Whittinghill and Rowe 2011)
-Using green roofs as the site for an urban
agriculture project can reduce a community’s urban
footprint through the creation of a local food
system.
-These projects can serve as a source of
community empowerment, give increased feelings
of self-reliance, and improve levels of nutrition.
f.Local Job Creation
-The growth of green roof and wall market
gives new job opportunities related to
manufacturing, plant growth, design, installation,
and maintenance.
-American Rivers suggests that a USD $10B
investment could create 190,000 jobs by building
48.5 billion-square-feet of green roof area, or just
one percent of the United States’ roof space in
every community over 50,000 in population.
-There is significant potential for new
growth in dense urban areas that were previously
unusable.
g.Marketing
-Green roofs can increase a building’s
marketability. They are an easily identifiable symbol
of the green building movement and can act as an
incentive to those interested in the multiple
benefits offered by green roofs.
-Green roofs, as part of the green building
movement, have been identified as facilitating
(Wilson 2005):
-Sales
-Lease outs
-Increased property value due to
increased efficiency
-Easier employee recruiting
-Lower employee and tenant turnover