Comfort Systems USA, Inc. engages in the provision of mechanical and electrical contracting services. It operates under the Mechanical and Electrical Services segments. The Mechanical Services segment includes heating, ventilation, and air conditioning, plumbing, piping, and controls, as well as off-site construction, monitoring, and fire protection. The Electrical services segment focuses on installation and servicing of electrical systems. The company was founded by Alfred J. Giardinelli, Jr. in December 1996 and is headquartered in Houston, TX.