Waltham’s eco-friendly home builder Blu Homes Inc. is expanding to the west coast, opening a new office in San Francisco.

Paul Warner, former president of Michelle Kaufmann Designs, and new creative director for Blu’s mkDesigns line, will run the west coast design team. Other key players included Blair Porteous, director of West Coast operations, and Milli Josifovska, West Coast sales associate.

"California is both the heart of America’s green movement and its advanced technology center, so we are excited to be expanding our presence here," said Bill Haney, founder and CEO of Blu. "As one of America’s most talented and experienced architects of green, prefab homes, Paul Warner played a central role in designing the original Glidehouse and Breezehouse, and in overseeing the construction of more than 30 of these beautiful homes across the West Coast. We are delighted to have him lead our team to upgrade these extraordinary designs, using our advanced proprietary technology to bring them conveniently and cost effectively to families across the region."

Warner is a registered architect and a licensed contractor in California and has been designing beautiful green prefab homes for 15 years, according to a statement.