Construction company Skanska has been rated the number one green builder in the Green Contractors Survey conducted by McGraw-Hill’s Engineering News-Record. The survey ranks the top 50 contractors in the U.S. for green building practices.

Companies that made the top ten of the survey are the Turner Corporation, Bovis Lend Lease, Swinerton, DPR Construction, Hunt Construction Group, Gilbane Building Company, Hathaway Dinwiddie Construction, William A. Berry & Son, and Clayco.

Skanska USA Building was the first construction management firm to have all of its environmental management systems registered to the ISO 14001 standard, and the company also built the first LEED Gold hospital in the U.S. at Providence Newberg Medical Center in Newberg, Oregon, according to McGraw Hill. Skanska has built many other LEED-certified projects, including the LEED Gold Waterfront Technology Center in Camden, New Jersey, and the first LEED Certified airport terminal in the U.S.: Delta Air Lines’ Terminal A at Boston’s Logan International.