Canada Mortgage and Housing Corporation

Canada Mortgage and Housing Corporation

December 05, 2012 10:40 ET

Layering Up for Winter: Insulation Retrofits for Your Home

OTTAWA, ONTARIO--(Marketwire - Dec. 5, 2012) - If you own an older home, chances are that you are always on the look-out for ways to reduce your heating costs. Adding insulation to your home not only helps you save money right now, it's also a way to "future proof" your home, protecting you against energy cost increases down the road. As well, a well-insulated energy-efficient home reduces the need for cooling in the warm months. A well-insulated energy-efficient home also reduces the need for cooling in the warm months.

By far the best time to upgrade your home's insulation is when you are doing other renovation work. For instance, it may not make much economic sense to remove the exterior cladding on your home simply to add more insulation, but if you are replacing the cladding because it is worn or you want to upgrade the curb appeal of your home, this is the perfect time to add insulation to the outside of the walls and to seal up leaks. Fortunately, there are many different options to achieve different levels of energy performance in typical older homes by adding insulation to the attic, walls and foundation and reducing air leakage.

Increasing Energy Performance

The first step should always be to make your house more airtight. Use caulking and spray insulating foam to close up gaps around windows and doorways and under thresholds. Inspect and replace worn weather-stripping and seals on windows and doors. Add foam gaskets behind the face plates of electrical outlets and switches on exterior walls. Seal around outside faucets and vent hood. Doing this reduces drafty spots, making your home more comfortable, reduces exterior noise and dust, and actually helps the insulation you have in your house work better.

Air sealing is also one of the least expensive and most cost-effective energy saving retrofit measures you can do. Without it, you will not gain the full benefit of increasing the existing insulation in your home as air leakage can reduce the effectiveness of many types of insulation.

You can save up to 10 per cent on the space heating costs for a typical older home by improving the air tightness of the home by 30 per cent and adding an additional R20 worth of insulation in the attic, R10 on the basement walls, or R10 in the above-grade walls. The cost can range from $7,500 to $15,000 or more, depending on the insulation you choose, how much you install, other renovation work you are having done, and, how energy-efficient your house is to begin with.

To reduce your space heating costs by 25 per cent, you may need to improve the air tightness of the home by 30 per cent, add another R20 in the attic and R15 to the exterior and basement walls. This work can cost anywhere from $18,000 to $30,000 or more depending on the full extent of the actual work that needs to get done.

Alternatively, instead of adding insulation, you may be able to achieve the same 25 per cent goal by installing new Energy Star®-rated windows. The cost of new windows is in the order of $15,000 or more depending on the number of windows to be replaced and the features selected. Ensure any new windows are well-sealed into their wall openings as air leakage can undermine their insulating value.

It is important to consider the effect of adding insulation and air sealing on the whole house. While improved air tightness goes hand in hand with reduced drafts and heat loss, it also reduces the amount of fresh air that can leak into your house, leading to moisture build-up and lingering odours if not balanced with energy efficient ventilation - a heat recovery ventilator, for example. This is the reason that "build tight-ventilate right" has been the credo of energy efficient builders and renovators for over 30 years.

Keep in mind that it is always a good idea to get an energy audit done of your house before you decide what to do and how much to invest. To formulate specific retrofit plans for your house, CMHC recommends that you retain the services of a qualified residential energy service provider to undertake an EnerGuide audit. Audits and ratings can be obtained from service organizations licensed under Natural Resources Canada's EnerGuide program. For more information on finding a qualified service organization, visit

CMHC has a wide range of helpful information for homeowners on sustainable technologies and practices and renovating for energy available from or by calling 1-800-668-2642.

For over 65 years, Canada Mortgage and Housing Corporation (CMHC) has been Canada's national housing agency, and a source of objective, reliable housing information.

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