Superior Plus Construction Products Distribution
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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.


Winroc was founded by Wayne Jack in 1971 as a single store in Winnipeg, Manitoba. Mr. Jack used personal savings and a private loan to create the retail building materials supply business offering one-stop shopping.


A decade later, in 1982, a leading U.S. commercial and industrial insulation and specialty contractor founded Specialty Products & Insulation Co. (SPI) as a subsidiary to serve the distribution segment of the mechanical insulation industry.

Meantime, Winroc was gaining a foothold in Western Canada, purchasing Alberta Drywall Supplies, the first in a series of acquisitions which would contribute to the company’s steady future growth.


In the mid-1990s, Winroc moved into Arizona and Minnesota, followed by Utah and Nevada in 1998 and 1999.

Late 1998, SPI separated from its parent, Irex Corporation, and began operating as an independent company.

2000 & beyond

Winroc was acquired by Superior Plus in June 2004. Joining Superior Plus allowed Winroc to further grow its operations to serve customers in new regions in Ontario, the Maritimes, British Columbia, and the U.S.

Superior Plus acquired SPI on September 24, 2009, complementing its Canadian businesses units.

Allroc Buying Group

The creation of the Allroc buying group in the mid-1970’s with partners in Vancouver and Regina became a major strategic advantage for Winroc, providing access to more high-quality products and suppliers than individual stores could secure on their own. On the very day it launched operations, Allroc was the largest buyers of wall and ceiling products in Canada. Today, Allroc is still one of the country’s largest gypsum buyer and one of the largest in North America.