Windows

Heat gained or lost through inefficient windows can increase the energy used to heat and cool your home by 25 to 30 percent.

Energy-efficient windows have:

• Special coatings (known as low emissivity coatings, or “low-E glass”) and insulated frames and sashes which will reduce the cold transfer from outside and condensation on the glass
• More glazing (panes of glass) for better exterior noise reduction and even more energy savings
• Special inert gases between the glass panes rather than just air for better insulation
• A label on the product to indicate where the model is certified for use in Canada

What to Look For

• A low U-value. The U-value is a measure of the window’s insulation value. Look for windows in the range of 0.25 to 1.25, with 0.25 being the best
• Buy windows certified for installation in Canada. In Canada, all windows should be at least double-glazed – two panes of glass
• Windows with more glazing (panes of glass) and low-E glass are the most efficient
• Hinged windows (casements, awnings, hoppers, tilt-turns) are more air-tight than sliders

Things to Consider

• Purchase ENERGY STAR® certified windows
• Windows that don’t open are more energy-efficient, but floors with bedrooms require at least one window that opens for an emergency exit
• The window frame affects a window’s insulation value, strength, maintenance, and longevity. Wood and fibreglass frames are the most efficient
• Hire trained installers to ensure your windows and skylights will perform their best.
• Window and supplier warranties vary. Compare before you purchase
• Consider installing high insulation value windows on the east and north sides of your house to reduce heat loss
• Consider getting an EnerGuide home evaluation to help you understand how your home uses energy and identify all improvement opportunities
• Check with your municipality, utility, or retailer to see if rebates are available

Source: Natural Resources Canada