CNR

Cornerstone Building Brands, Inc.

A maker of the outside of buildings — windows, vinyl siding, doors, stone veneer, and metal roofing and framing — sold under well-known brands like Simonton, Ply Gem, and Star Building Systems. The company was formed in late 2018 when metal-building maker NCI Building Systems merged with window-and-siding giant Ply Gem. The new name "Cornerstone" was chosen because a cornerstone is the first stone set in a foundation — a nod to the foundational role its products play in homes, schools, and hospitals.