You came here to learn how to fix a hot attic, so let’s jump right in.
Why Do Attics Get So Hot in the Summer?
As I said before, there are several things that could be contributing to your hot attic.
First, we have to talk about science. Remember the first time you learned about how heat rises? In the winter when you heat your home, that heat can rise right up into the attic. This poses a problem because all that air you’re paying to heat is going up right into the attic and out.
If you have insulation on your attic flat that allows for air movement, then your warm air gets through but will also stick up there. Another thing that comes into play here is proper venting and if you don’t have it in the soffit vents, ridge vents, or gable vents then you’re trapping heat up there.
The same is true for the summer, except it is hot air coming into your home and traveling up to the attic and then you also have the sun to contend with.
The sun is beating down on your roof throughout the day and is turning your attic into an oven.
Now, if you have that problem, combined with improper venting or blocked venting, you’re just making the issue that much worse. Our crews have been in plenty of attics where it’s super-hot, I mean we’re talking 140- to 150-degrees or more. I’ve even seen situations where the wood trusses are so hot to the touch you wouldn’t be able to hold them for very long. If there are metal ducts in the attic, you can actually burn yourself.
These are just a few of the reasons your attic is doubling as a sauna. We’ve covered why attics get so hot in the summer, now let’s discuss how to cool down a hot attic.
Hot Attic Solutions: How to Cool Down a Hot Attic
Let’s talk about how insulation can help cool down your attic.
If you have insulation on the roof deck of your attic, you don’t want to have any vents up there. The way this insulation system works is the attic floor should be clear of insulation. This way the heat will come up into the attic, circulate around and back down into your house. This is especially true if you use an insulation material that creates an air seal.
As the air heats, it will rise, cool down, and fall back into the rest of your house. You want the air in your home to circulate throughout the house just like this and insulation on the roof deck helps with this.
If the attic flat is insulated and you have no venting or the venting is blocked, then there is no easy way for the air to circulate back down creating a very hot attic.
This is why insulating the roof deck can be the best option to combat that super-hot attic.
Fixing Your Hot Attic and Keeping Your Home Cool in the Summer
The attic might not be the only trouble spot that is hotter than you’d like.
You know how to fix your hot attic, but what about the rest of the house?
Insulating the building envelope of your home can help make it a conditioned space. Depending on the insulation you choose, insulating the entire building envelope, which is essentially the parts of your home that separates the outdoor environment from the interior of the house, will slow down or stop air leakage.
That air leakage is responsible for your house feeling much hotter than you like.
One way to combat this is by creating the air seal I mentioned earlier with foam insulation.
If you’d like to learn a few other ways to keep your home more comfortable and energy-efficient, check out the Learning Center on our website. Another great place to find helpful resources is on our YouTube channel where you can watch me talk about all things insulation on Foam University.
Eric brings his knowledge and training in building science, training in spray and injection foams from the manufacturers, more than 8 years installing foam insulation, as well as selling and managing in the foam insulation industry. He is also BPI and Dale Carnegie certified and has taken several building science courses including air sealing and building envelope.
Eric’s responsibilities include overseeing and giving support to all of the branches of the RetroFoam of Michigan company, office, estimates, and installs. He is also the Professor of Foam on our educational YouTube series Foam University.
Even when Eric is off he is usually still “working” or thinking about work, but when he can get away he enjoys camping, hiking, hunting, and woodwork.