To help mitigate greenhouse gas (GHG) emissions and meet the city's climate goals, Denver, Colorado, created the Green Buildings Ordinance (GBO), a community-initiated regulation which required the city's large buildings to install green roofs due to their environmental benefits. The GBO was later updated and included the addition of green roof alternatives such as cool roofs, on-site solar and LEED certification. In compliance with the latest update, new buildings over 25,000 square feet are now required to install a cool roof as well as a green roof or alternative, while existing buildings under 25,000 square feet must meet the same requirements but only when replacing the roof.

 

Commercial and multifamily buildings are reported to be the cause of more than half of the city's greenhouse gas emissions. The Green Buildings Ordinance was implemented to help lower these emissions and also reduce urban heat island effects, improve air quality, reduce rainwater runoff and increase building performance through energy efficiency. Results from the first partial year of the GBO showed a total of 51 construction projects have installed a cool roof and one of the additional ordinance requirements. As of July, seven projects have complied by acquiring LEED certification. Denver continues to work towards sustainable solutions to climate change in hopes to meet their goal of an 80% reduction in GHG.