When you’re insulating your house, it’s important to use the right material for the job.
This is especially true for exterior walls – you don’t just need to worry about keeping your home warm, but you also need to make sure that it can endure the elements that your exterior walls face.
It can be hard to even know where to start when it comes to insulating your exterior walls, and picking the right insulation material can be tough.
Luckily, we’ve done all the hard work for you!
In this handy guide, we’ve gathered some of the best options for insulating your exterior walls, looking at their benefits as well as some of their downsides.
So let’s jump right into it and take a look at the best insulation for exterior walls!
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5 Best Insulation Materials For Exterior Walls
1) Fiberglass Insulation
Fiberglass insulation has been around for years, and its popularity will likely only continue to grow in the coming years.
It provides great energy efficiency while being very affordable, making it an excellent choice for most people who are on a tight budget.
Fiberglass insulation works by filling the air pockets between the studs in your wall, which helps keep heat from escaping through those areas.
Because fiberglass insulation doesn’t expand or contract with changes in temperature, it won’t crack or break like other materials might.
And because it’s made up of glass fibers, it’s extremely durable and resistant to moisture damage. To top it all off, it’s almost completely fireproof.
However, there are some drawbacks to using fiberglass insulation. First off, it’s not nearly as environmentally friendly as cellulose insulation (which we’ll get to next).
Second, it’s not as easy to install as many other types of insulation, and can slump and sag over time. This means that you will probably have to replace it after a couple of years.
But if you want something that’s going to last for a while and do its job well, fiberglass insulation is definitely a good choice
2) Cellulose Insulation
Cellulose insulation is one of the most popular choices for exterior walls, and for good reason.
It’s incredibly effective at stopping heat transfer, and it’s relatively inexpensive. Plus, it’s very easy to install, so it’s perfect for DIYers.
This insulation material is made out of recycled paper and cardboard, which makes it a much more eco-friendly alternative to fiberglass.
It is also better at insulating against the cold, and is better suited to colder climates.
Cellulose insulation typically comes in two forms. Blown-in cellulose is made of shredded pieces of paper and cardboard, which can then be blown into your walls through holes made by yourself or the installer.
Another form that cellulose insulation is available in is batts.
These are compressed slabs of the material that are installed as panels inside your walls.
The increased density of these batts over blown-in cellulose insulation means that they are far more effective at dampening noise.
Like fiberglass, blown-in cellulose insulation has a tendency to shift and slide over time, leading to the same issues. Meanwhile, the batts are more difficult to install and require parts of the wall to be removed.
3) Spray Foam Insulation
Spray foam insulation is another popular option for exterior walls. Like fiberglass and cellulose, spray foam insulation is highly effective at keeping heat inside your home.
However, it does this without any of the downsides associated with fiberglass and cellulose, such as shifting.
In fact, it actually outperforms both of them when it comes to sound proofing walls and thermal performance.
It’s also an environmentally-friendly option that will last for years without needing to be replaced.
Spray foam insulation is installed similarly to blown-in cellulose insulation. Holes are made in the wall for the foam to be installed.
It is then sprayed through these holes into the wall cavity, where it will expand to fill in all the nooks and crannies within.
It then dries and solidifies, creating a barrier that prevents air moving in or out of the wall to keep your house warm without racking up a massive energy bill.
The main drawback to spray foam insulation is that it is very hard to remove if you get it wrong or need to replace it.
Because it dries into a solid, it is difficult to take out once it has hardened. This is also an issue if you have a problem with the electrical cables in your walls, as the foam makes it hard to access them.
4) Foam Board Insulation
Foam board insulation is one of the least common types of insulation used for exterior walls. But it is still worth mentioning because it is often overlooked.
While it isn’t as easy to install as some other forms of insulation, it is far more durable and can be used for decades without needing to be replaced. It’s also extremely cost-effective.
Foam board is simply sheets of expanded polystyrene (EPS), which is usually manufactured from scrap plastic bottles.
EPS is lightweight and strong, making it ideal for use as insulation. It is also rigid, and doesn’t move around like fiberglass or cellulose insulation, so it won’t cause problems with shifting or sliding.
It also lasts much longer than either of those materials, meaning that it will not need replacing for many years (if at all!).
However, there is a fairly large downside to installing foam board insulation that can be off-putting to some homeowners.
Because the boards are large and rigid, installation isn’t as simple as with spray foam or blown-in cellulose.
You’ll need to remove part of the drywall to put the boards in place, which can be a lot of effort and hard work. However, if you’re happy to do some remodeling then foam boards are a great option for you.
5) Injection Foam Insulation
This type of insulation is very similar to spray foam insulation, but there are a few differences between the two.
The most obvious difference is that injection foam is injected directly into the wall instead of being sprayed onto it. This means that it goes straight into the wall rather than expanding first before drying.
In addition to this, injection foam insulation is more expensive than spray foam insulation. It is also harder to install, which means that it may require professional help.
However, it is also much stronger and more durable than spray foam insulation. This means that it will last for many years without needing to be removed or replaced.
It also forms an airtight seal, meaning that your warm air will never leave your house. It won’t sag or slump, and is much easier to install in existing walls without the need to remove parts of the drywall.
There are many types of insulation that you can use in your exterior walls, each with their own benefits and drawbacks.
The right insulation for you comes down to a couple of factors, including cost, your climate, and the amount of work that you’re willing to do on your house for installation.
For instance, foam boards need the existing drywall to be removed before they can be installed, but their durability makes them one of the most cost-effective forms of insulation in the long run.
Meanwhile, blown-in cellulose is cheap and easy to install, but it doesn’t have the same longevity and can lead to issues down the road.
Whichever form of insulation you pick for your exterior walls, you can rest assured that it will keep your house at the perfect temperature and prevent the loss of heat.
Proper insulation is important, and keeping your house well-insulated will lower your energy bill, reduce your carbon footprint, and keep your house warm in the colder months and cool when it gets too hot!
So now that you’ve been able to look at some of the best options out there, all that you have to do now is make your pick!