CertainTeed Corporation is a leading North American manufacturer of building materials including roofing, siding, insulation, windows and patio doors, fence, decking, railing, foundations and pipe. The company is headquartered in Valley Forge, Pennsylvania, and has approximately 9, 000 employees and 70 manufacturing facilities throughout the United States. CertainTeed is a subsidiary of Saint-Gobain, one of the top 100 industrial companies in the world. Saint-Gobain employs approximately 26, 000 people in North America and more than 170, 000 people in 46 countries worldwide. Saint-Gobain�¢??s North American companies operate nearly 200 manufacturing facilities in industries as diverse as industrial ceramics and containers, reinforcements and flat glass, abrasives, and building materials.