New York City passed its NYC Climate Mobilization Act in 2019 to stiffen rules, with "long-term and wide-ranging fiscal and operational impacts for building owners, buyers, sellers, lenders and tenants," as law firm Stroock & Stroock & Lavan described.

Part of it included the need for new buildings or those facing specific types of renovations to include either a green roof — using vegetation to make buildings less susceptible to hear — or one with solar panels to general electricity. Except a that proptech company Archipelago recently verified a study from last fall suggesting that hardly any building has complied.

Last fall, a study in Ecology & Society by researchers from The Nature Conservancy, Wildlife Conservation Society, The New School's Urban Systems Lab, and CIESIN at Columbia University, used publicly available aerial imagery looking at the rooftops of the buildings that make up approximately 20% of the landscape. Out of more than 1 million buildings in New York City, they could identify only 736 with green roofs, less than 0.1% of the total, although they noted there could be others they hadn't been able to identify. Most were in midtown and downtown Manhattan. Other areas had "few to none."