If you are unfamiliar with a green rooftop, they are rooftop gardens installed to slow runoff, and reduce heat radiation in urban areas. Green rooftops are the wave of the future. Cities throughout the country have passed laws, some of which make installation mandatory in new structures, or when a roof is replaced. Colorado's Denver Green Roof Initiative is one of the strictest in the nation, according to the Denver Post. So, what should you be aware of when it comes to green rooftops?
Benefits of green rooftops
Green rooftops combat urban heat, which is heat absorbed by asphalt and concrete that contributes to the heat island effect seen in cities. Green rooftops also combat urban flooding, because storm water runoff is slowed when it percolates down through the growing media, reducing the rate of discharge coming out of storm drains. Depending on the composition of the growing media, contaminants and nutrient loads may be absorbed, which prevents discharge into our water sources. Green rooftops also increase energy efficiency in various ways by reducing urban heat, which lessens the need for air conditioning and acting as an insulator by preventing both hot and cold air from escaping the building.
Potential legal issues
Green rooftops require a different approach to building contracts. There are a variety of legal issues that may arise during and after construction, such as compliance with the U.S. Green Building Council's Leadership in Energy and Environmental Design (LEED) program, a ratings system that certifies projects that meet specific building criteria. Issues may arise if the green rooftop system fails to meet the stated energy efficiency rating, which provides tax credits or other financial incentives for builders and homeowners.
Maintenance of the rooftop could also be a potential area of liability. If the rooftop garden is incorrectly or inadequately maintained, a building could end up with mold damage, roof collapse, or in times of drought, increase the risk of fire. There may be issues with the irrigation system, or weed problems requiring renovation. Who should be responsible for communicating and dealing with these risks? Due to the unique nature of these projects, you should allocate risk between parties in your contract to balance potential liability.