We normally think of insulation as a tool to keep our homes warm in the winter. But it’s just as important to have proper insulation to help keep us cool in the heat of the summer.
In fact, proper home insulation – paired with a well sealed home – is a four season solution to keep you comfortable and increase your home’s energy efficiency at the same time.
In this article we explore:
- Why our homes are working against our best efforts to keep them cool
- How insulation keeps us comfortable in hot and cold weather
- How almost all of our homes are under-insulated
- How proper insulation saves you hundreds of dollars on your energy bill each year
- How to quickly check if your home is part of the under – insulated majority, and what to do about it
The problem
Warm air is always moving from warmer to cooler areas. In the summer, this means that the hot air from outside finds its way into our homes. During colder months, our heated indoor air flows in the opposite direction.
This air is constantly seeping through the exterior walls, windows, doors, and other openings of our homes.
This is why many of us crank up the air conditioning even higher during the summer (if we have it in the first place), only for more warm air to creep in before the AC has a chance to cool things down. This creates a continual loop of discomfort – for both our body temperatures and our wallets.
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How insulation helps
When it comes to soaring summer temperatures, proper insulation installed in your attic, walls, and floors will reduce the amount of the heat coming into your home. It does this by providing resistance to the flow of warm air, keeping more of it out.
When it comes to energy use and cost, the right amount of high-quality insulation can contribute to an average savings of 15% on heating and cooling.
This is equal to between $200-$400 dollars of savings over a year for most people – all while it helps keep ourselves and our loved ones safe from scorching outdoor temperatures.
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Does your home need more insulation?
Research from the U.S. Environmental Protection Agency shows that 9/10 homes in the United States do not have enough insulation to help prevent air exchange with the outside for maximum temperature control and energy efficiency.
In Canada, 8/10 are considered under-insulated, driving both bills and indoor temperatures up in summer months.
There are a few steps that you can take – or hire a contractor to do for you– to make sure you have enough insulation.

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Check insulation levels
This may seem intimidating, but it’s actually pretty easy to do yourself.
The easiest place to check insulation levels is in an unfinished attic. Most of the time, structural elements like joists, which are the pieces of wood that run horizontally between the walls, are visible in these areas. This makes it easy to see how much insulation there is without having to open anything up.
If your insulation is at or below the level of your joists, you likely need more.
If you don’t have an attic, you can also look behind the power outlets in your walls. Start by turning off all the power and using a voltage tester at the plug to make sure it’s really off.
If you don’t have a voltage tester, you can double check that the power is off by plugging in a lamp or small device and seeing if it turns on.
Remove the plate and check behind the outlet with a flashlight to see how much insulation is in your walls. It is recommended that exterior walls are completely filled with insulation, so you shouldn’t see any large gaps.
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Add more if necessary
If you, or a loved one, enjoy being handy, this Energy Star guide will walk you through the steps to add more insulation to your home. It’s rated as a moderate to difficult task to do by yourself.
For most of us, this step will involve hiring a contractor to come in and install the right level of high quality insulation throughout our homes. You can do a Google search and find the right choice of contractor based on Google reviews, or see if a trusted friend or neighbour has a recommendation for you.
A contractor will know exactly what kind of insulation is best, as well as what levels are necessary based on your home’s structure and the climate in your area.
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While it may come with an added price tag if you have to install more, it pays for itself in energy savings in three to five years – and after that it’s money in the bank!
Insulation is important, and once you’ve ensured that you’ve got enough of it you should give yourself a pat on the back. The other important piece to make sure you aren’t losing air – and energy – to the outside is ensuring that your home is well sealed.
Next week we will share our top recommendations for a well sealed home. Sign up to become a member today and it will be delivered straight to your inbox next week!


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