An amazing amount of thermal energy is lost in a home because of air leaks in flooring, windows, doors, etc. that allow the ingress of cold air. To maintain an even internal temperature more heat energy is required which translates to an increased consumption of fuel or electricity. It is hence imperative to properly air seal a home.

The first step is to identify air leaks. The ideal way of doing this is to have a professional carry out an energy audit which would include a blower door test. This in effect depressurizes a home with a view to identifying the leak sources.

A similar test can be done by the homeowner by using the following steps:

• Identify the obvious areas at the meeting point of different materials like brick and timber or between the walls and foundation.
• Check out door and window frames, flooring seams, outlets for cable TV, phone lines, gas and electricity connections, outdoor faucets, air conditioners, vents and fans.

A primitive manner of home depressurization would be to turn off the furnace, close all doors and windows and turn on all exhaust fans that draw air outside. Using an incense stick or a lighted candle, try to trace any drafts. If there is a leakage the trail of smoke will indicate it and so will the lighted flame of the candle.

Air leaks once identified should be attended to using techniques of air sealing like caulking and weather stripping. Fiberglass insulation and urethane foam are two materials commonly used in air sealing.

The effects from remedial measures after such a study can be very impressive. It is not unusual to reduce overall house leakages by 30% to 50% with commensurate savings in energy utilization.