WASCO Windows opened in Milwaukee in 1957 as Wisconsin Aluminum Supply Company, and was purchased by Dave Paulus in 1983. At that time, the company manufactured aluminum storm windows, siding and awnings.  Under Paulus’ direction WASCO became the first company in this area to manufacture then-new vinyl replacement windows. Since 1983 the Paulus family has transformed WASCO into a company that leads the industry in manufacturing and installing highly energy efficient window products, engineered for Wisconsin’s unique climate.

In 2012, WASCO fabricated the first American-made version of an energy-efficient, environmentally friendly window system that achieves European Passivhaus standards – and far exceeds North American Energy Star standards using the GENEO™ System (pronounced gun-ā-oh) of windows and doors, developed by the German company REHAU, world renowned for its ground-breaking technology and the unmatched quality of its doors and windows. In 2014 WASCO achieved PHIUS (Passive House Institute U.S.) certification on the GENEO window. PHIUS is a 501(c)3 organization committed to making high-performance passive building the mainstream market standard. Founded in 2007, PHIUS has trained more than 1,000 architects, engineers, energy consultants, energy raters, and builders, and is the leading certifier of passive buildings, with more than 100 single and multi-family projects certified or in process.