According to a recent article in earth2tech by Justin Moresco, mainstream homebuilders are starting to take energy efficiency and other green features a lot more seriously. The latest evidence came earlier this week when KB Home, one of the top five U.S. homebuilders, announced that all of its new developments in Northern California would be built to GreenPoint Rated standards, a green building rating system developed by Berkeley, Calif.-based Build It Green that grades homes based on energy efficiency, water and resource conservation, indoor air quality and more. “The early adopters were custom builders who championed the [GreenPoint Rated] standard,” David Myers, Build It Green’s communications and development manager, told us. “Now we’re seeing it move into the mainstream.”