If you own an older home, chances are, you’re always on the lookout for ways to reduce your heating costs. Adding insulation to your home not only helps you save money right now, but it’s also a way to “future proof” your home – protecting you against energy cost increases down the road. A well-insulated, energy-efficient home reduces the need for heating in the cooler months and cooling in the warmer months.
By far the best time to upgrade your home’s insulation is when you’re 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’re replacing the cladding because it’s 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 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 faceplates of electrical outlets and switches on exterior walls. Seal around outside faucets and vent hoods.
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 complete. Without it, you won’t 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% on the space heating costs for a typical older home by improving the air tightness of the home by 30% 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%, you may need to improve the air tightness of the home by 30%, 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 be done.
Alternatively, instead of adding insulation, you may be able to achieve the same 25% 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’s 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 more than 30 years.
Keep in mind that it’s always a good idea to get an energy audit of your house completed before you decide what to do and how much to invest. To formulate specific retrofit plans for your house, Canada Mortgage and Housing Corporation (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 http://oee.nrcan.gc.ca/residential.
CMHC has a wide range of helpful information for homeowners on sustainable technologies and practices and renovating for energy available from www.cmhc.ca or by calling 1-800-668-2642.