The Denver Green Roof Initiative has cleared the petition threshold to make the Nov. 7 ballot, the Denver Elections Division confirmed.

Backers of the initiative were notified Aug. 29 that the Elections Division verified 4,771 signatures on their petition as coming from valid registered city voters — just 45 above the 4,726-signature threshold. The group of environmental activists is led by Denver resident Brandon Rietheimer, and their aim is to reduce Denver’s urban “heat island” effect.

The ballot measure would require most new buildings of at least 25,000 square feet to have gardens, solar panels or other “green roof” components cover at least 20 percent of their roofs’ surface, depending on a building’s size. Roof replacements on existing buildings also could trigger the requirement.

The rules, if approved by voters, would be among the most stringent in the United States. But the ballot measure is likely to face opposition by developers and other building interests because of the costs it would impose.

The Denver Post examined the proposal in more depth in March 2017.