Construction Products Distribution (CPD) ... Is one of North America’s leading distributors of commercial and industrial insulation and specialty walls and ceiling products. It is the largest distributor of specialty construction products to the walls and ceilings industry of Canada. Through its operating divisions, Winroc in the Gypsum Specialty Distribution segment and Specialty Products & Insulation (SPI) in the Commercial and Industrial Insulation segment, CPD has 117 distribution centers, including 15 fabrication facilities, across North America with a presence in 28 states and five provinces. Winroc and SPI have business track records dating to the early 1970s and roots reaching back as far as the 1920s. History... On January 1, 2011, Specialty Products & Insulation Co. (SPI) and The Winroc Corporation (Winroc) – both members of the Superior Plus group of companies – merged into one legal entity in order to simplify our corporate structure. The new legal name is Superior Plus Construction Products Corp. Winroc and SPI are the leading distributors of walls, ceilings and insulation construction products in North America with long histories, and experience that runs deep.