Insulation and air sealing

A well insulated home uses less energy. That means lower heating and cooling costs and less environmental impact.

Whether it is cold air leaking in during the winter or warm air during the summer, a drafty house loses energy and is less comfortable. Insulating your home is one of the easiest and most cost-effective ways to save energy and lower your energy bill.


You can draft-proof your home by sealing the gaps and cracks with weatherstripping. Weatherstripping is used to control air leakage at the joints where 2 surfaces meet and move relative to each other such windows and doors. One way to detect air leaks is to make a draft detector by clipping a light tissue or plastic onto a coat hanger. If the tissue flutters when held against a window or door, there is an air leak.

Weatherstripping products are available in a wide range of material types, shapes, and colours suitable to your existing window and/or door system such as:

  • window and door gaskets;
  • weather strips;
  • door sweeps/bottoms;
  • door thresholds;
  • door jamb strips.

Window insulating film

Window insulating film is a plastic film that can be applied to your windows or doors to reduce the transfer of heat. This product is applied to the window or door frame and is designed to trap a pocket of air between the glass and film, acting like a temporary extra pane of glass. It is different than solar control films that stick directly to the glass and reduce glare. Window insulating film prevents frost and condensation, increases thermal resistance; is easy to install and remove, and it shrinks tight for a transparent, wrinkle-free fit. It is best to install the film on non-operable windows and doors in late fall/ winter.

Read our how-to booklets:

Sealing, caulking & weatherstripping (PDF, 847 KB).

Basement & crawlspace insulation (PDF, 841 KB).

Attic insulation (PDF, 671 KB).

Wall insulation (PDF, 625 KB).

Read more about insulation