By: Jim Borgel
In November’s general election, Denver voters approved the so-called green roof ordinance, which goes into effect on January 1, 2018. Under the ordinance, all new buildings in the City and County of Denver that are 25,000 square feet or larger, any additions to existing buildings that cause the building to equal or exceed 25,000 square feet, or a roof replacement on a building in that is 25,000 square feet or larger, must incorporate green roof technology into their design. A “green roof” is one that incorporates growing vegetation, and the percentage of the roof that must be green will vary depending on the size of the building. Buildings between 25,000 and 49,999 square feet will be required to have twenty percent of their roof surface green, while that percentage will increase to 60 percent on buildings over 200,000 square feet. The initiative will also allow a portion of the green roof requirement to be satisfied by the installation of solar panels, as long as at least 30 percent of the roof continues to be “green.” Residential buildings with a height of less than four stories or fifty feet are exempt from the green roof requirement, and in some instances the Denver Planning Board may approve exemptions to this requirement, although a cash-in-lieu payment equal to $25.00 per square foot the roof area that would otherwise need to be green must be paid by the applicant.