Home Insulation

Potential savings up to $2000 per year

The cheapest approach to domestic heating in Canada is to begin with a well-insulated house. One house, built in an Edmonton (the coldest Canadian city) suburb requires no heating! This house incorporated superb insulation. The warmth came entirely from appliances and lighting, plus the occupants’ ™ body heat. Even in winter, when guests were invited, windows sometimes had to be opened to cool the house! (A good rule might be “You can never have too much money, sex, or insulation”.) Unfortunately, except for the attic, it is expensive – even impossible – to add insulation to existing walls.

Roof Insulation

Depending on what is now under the your roof, and how much it costs to heat the house, the potential savings are huge. Blowing extra insulation under your roof is usually cheap (about $500 for a typical house – depending on size & depth of insulation desired) and very easy. Professionals can blow in loose-fill fiberglass in ½ an hour!

You can easily tell if this needs to be done. After a snowfall, check your roof for several days. If snow melts in patches when the air temperature is around -3oC to -5oC, this suggests that heat is being lost from the living space. At -10oC or below, snow will probably not melt on your roof.

If snow is melting on the roof, there could be nothing wrong with the insulation. The problem could be poor sealing around, or poor insulation of the access hatch to the roof space. That is a very cheap “fix” and should be checked first. Icicles are a pretty winter sight. However, you do not want them on your house ever!

Icicles are a sign of very poor roof insulation. They are caused by snow melting continuously on the roof. The water re-freezes as it drips to create the decoration. An icicle-decorated house could waste well over $1000 of heat every winter and should be seen to immediately! Icicles are the most expensive Christmas ornament your house can have! If you are interested in home products in Canada, pay attention to the buying guide & reviews from NRR.


A very important part of insulation is draft-proofing. If you can identify drafts, put in the appropriate draft-proofing measures as soon as possible. Sealing windows, doors and other potential draft sources is the very cheapest way to lower heating bills. If you cannot identify specific drafts, see the paragraph below on Energy Audit.


Never Overdo Draft-Proofing!

Beware of sealing your house too well! If your furnace takes indoor air (low & mid-efficiency units do), sealing your house can “starve” the furnace of air, causing it to produce carbon monoxide. This can poison your family!

Fireplaces and other home appliances need fresh air, too. Your drier takes indoor air, heats it, and then exhausts the moist air. It may be unable to operate properly if the house is too well sealed. The same applies to your stove vent, bathroom fan and fireplace. So, after sealing the drafts into your living space, make sure that enough air can enter the house preferably into the basement near your furnace. That way the incoming air will cause no discomfort and add little to your heating costs.

Sealing your house too well could also cause moisture to condense on windows, windowsills, and even inside the walls unseen! The latter problem could allow mould to grow, cause wood to rot, and can reduce the effectiveness of nearby insulation.

There is a way to allow fresh air to enter, but not lose heat . . .

Heat Recovery Ventilator

This clever device exhausts “stale” inside air and pulls fresh air into the house. It allows the warm outgoing air and cool incoming air streams to exchange heat, cooling the stale air and warming the fresh air. There are various ingenious designs. In the simplest, the incoming and outgoing air flow side-by-side; heat exchange occurs across a thin metal wall.

Heat recovery ventilators ensure that moisture and pollution (cooking, smoking, excess moisture, etc) do not accumulate inside an otherwise well-sealed house. Such devices have been required on all Scandinavian houses over the last 30 years or so. Their efficiency varies from around 60% to 75%; meaning that 60 -75% of the heat leaving the vent is captured by the fresh air entering. Of course, this type of unit prevents cold drafts from sneaking under poorly sealed doors, improving indoor comfort. The incoming air is often introduced into the cold air return of a warm air furnace.

About 5% of Canadian homes have HRVs. Some provincial building codes now require them in new houses.

Thermostat Setting Potential savings ~$200 per year

A very simple approach to energy savings is to lower the thermostat setting. The rate of heat loss depends on the difference between inside and outside temperature. Taking the average outside winter temperature as -5oC, if the indoor setting is reduced from 23oC to 18oC, heat loss (heat demand from the furnace) should be reduced by 5/28, or over 20%.

If you hate to be uncomfortable, then lower the temperature while the house is unoccupied, and overnight when you are asleep. The savings will be reduced, but could still be substantial. Nighttime re-setting (8 hours) alone should lower heating bills by 7%. Expanding this to the hours the house is unoccupied during the day (8 hours) should double the savings.

Automate the re-setting process. For less than $100, you can install a programmable thermostat to do the job for you.

Energy Audit

If you feel drafts, but cannot identify the source, arrange for an energy audit on your house – including a Blower Door Test. The Blower Door is a powerful fan temporarily sealed into an outside door frame. With all windows and doors closed and the fan on, the inspector checks the house for drafts. The air pulled into the house makes even small drafts easy to spot. How drafty your house is may be vividly described: “like an open pet door”!

Drafts may come via light switches and electric outlets in outside walls. They may come up through the floor from a crawl space, an attic hatch, a poorly fitted basement window, etc.

A proper energy audit will take 2-3 hours and cost $50-$300, depending on whether it is subsidized by a utility or the municipality. Energy auditors will tell you how to improve on your home’s energy performance. They may also give advice on saving water, composting, recycling and other “green” stuff. Finally, an energy auditor should give your house an EnerGuide Rating, like the ratings on modern electrical appliances. A good EnerGuide Rating can be a convincing selling point.

If your annual heating bills are $1500 or more, an Energy Audit will be money very well spent!

Home Insulation