Cornerstone Building Brands, Inc., together with its subsidiaries, designs, engineers, manufactures, markets, and installs external building products for the commercial, residential, and repair and remodel markets in the United States, Canada, Mexico, and internationally. The company operates through three segments: Windows, Siding, and Commercial. Its Windows segment provides vinyl, aluminum, wood, and aluminum clad-wood windows and patio doors and steel, wood, and fiberglass entry doors under the Ply Gem, Simonton, Atrium, American Craftsman, Silver Line, Great Lakes Window, and North Star brands. The company's Siding segment offers vinyl siding and skirting, composite siding, steel siding, vinyl and aluminum soffit, aluminum trim coil, aluminum gutter coil, fabricated aluminum gutter protection, PVC trim and moldings, and window and door trim products, as well as injection molded accents, such as shakes, shingles, shutters and vents, vinyl fencing and railing, and stone veneer. Its Commercial segment designs, engineers, manufactures, and distributes a range of metal products, such as metal building systems, metal roofing and wall systems, and coil coatings. The company was formerly known as NCI Building Systems, Inc. and changed its name to Cornerstone Building Brands, Inc. in May 2019. Cornerstone Building Brands, Inc. is headquartered in Cary, North Carolina.