Go Green at Home
A green roof is partially or fully covered with vegetation planted in a growth medium over a waterproof membrane.
Green roofs can lower utility bills by acting as insulation on the roof and decreasing the need for air conditioning by reducing solar radiation. The reduction in heating and cooling costs can be significant depending on the size of the green roof compared to the overall size of the building roof. Although installation costs are higher than traditional roofs, if properly maintained green roofs will last longer than traditional roofs resulting in lower costs over the long-term. Building roofs need to be strong enough to hold an additional 10-50 pounds per square foot in order to accommodate the saturated weight of a green roof. Buildings that commonly have green roofs include hospitals, stadiums, airports, commercial and industrial buildings, and flat roofed apartment buildings with social areas.
Plants, including those installed as part of a green roof, filter rainwater removing sediment and nutrient pollutant from runoff. Every time it rains, water moves across traditional roofs picking up any sediment, nutrients, metals or other materials deposited on the surface of the roof. Water moves from your roof into your downspout and out into the storm drain. Once in the storm drain system, polluted runoff is carried directly to the Wabash River. Installation of a green roof can reduce up to 95% of the volume of polluted runoff from your property. The more water you retain on site, the less water flows across the land surface resulting in less sediment and nutrient polluted runoff flowing directly into the Wabash River. Additionally, green roofs absorb pollutants from the air filtering these before releasing dissolved oxygen into the air and provide habitat for insects and birds.
Although materials to build a green roof are not readily available locally, two green roofs offer examples of how green roofs looks once installed. Schleman Hall (475 Stadium Mall Drive, West Lafayette) and the City of Lafayette’s office at 515 N. Columbia Street, Lafayette both include green roofs. Stop at Schleman Hall for a self-guided tour or at the City of Lafayette’s office for a personal look at the structure.
Purdue Publication: Purdue’s First Green Roof
Green Roof Contractors:
Knickerbocker Roofing and Paving