S.I.S. offers a selection of high-quality windows and doors for the Calgary construction and window replacement and door replacement markets. We also focus on custom siding and framing for residential and light commercial projects throughout Calgary and surrounding communities. Besides siding and roll shutters, S.I.S. is one of the leading installers of windows and doors Calgary has to offer. As a Certified Window Wise Dealer, our window installations, including replacement windows, are backed up by approved windows, certified installers, random job inspections and a Quality Assurance Guarantee.