Great Northern Insulation is Canada's Contractor of Choice for Building Envelope Solutions.\n\nOver the past 39 years, Great Northern Insulation has increased the comfort, energy efficiency, and durability of buildings and homes throughout Ontario. We provide a wide variety of insulation, air sealing, and weatherstripping solutions for both residential and commercial projects.\n\nAt GNI, we exceed customer expectations by delivering professional service, quality installation, and excellence in building performance. Contact us today and discover how we can save you money on your heating and cooling costs while increasing your home comfort year round!