Founded in 1972, Thermo-Twin Industries is an employee-owned window manufacturing company. Headquartered in Oakmont, Pa., it also maintains showrooms and offices in Virginia, New York and Ohio. The company provides vinyl, aluminium and garden windows in a variety of designs, such as single and double hung, casement, horizontal sliders and hopper. Thermo-Twin Industries offers studios and roof furnishings, sunrooms, patio and seasonal rooms. It also provides sliding glass and entrance doors. The company operates retailer, wholesaler and commercial divisions. Additionally, Thermo-Twin Industries offers vinyl siding for historic renovation, remodeling and new construction purposes. It provides installation, maintenance, renovation and replacement services.