When insulating your home, it’s essential to cover all spaces, including the dryer vent. The issue with not insulating the dryer vent is that heat can escape through it, making your home less energy efficient.

Spray foam is a great way to insulate the dryer vent. It’s easy to apply and provides a great sealant. Plus, you can find spray foam at most hardware stores.

But it’s important to know which type of insulation to use on the dryer vent, as some types can be a fire hazard. Closed-cell foam is a better option than open-cell foam since it’s less flammable and doesn’t expand too much to crush the dryer vent. Here’s an overview of how to use spray foam around dryer vents. 

Is It OK To Insulate Around A Dryer Vent?

Typically, you don’t have to insulate the dryer vent. But if it runs through an unheated basement, crawl space, or unconditioned space, you should insulate around it to prevent heat loss.

You can use spray foam insulation around the dryer vent, but make sure it’s labeled as fire-resistant. You can also use other types of insulation, such as fiberglass batting or mineral wool.

The key is to ensure no gap between the insulation and the pipe. If there’s a gap, heat can still escape.

What Kind Of Insulation Can You Put Around A Dryer Vent?

You can use different types of insulation around a dryer vent. Some good options include the following.

Foam Board Insulation

Foam board consists of two foam panels with a plastic or paper liner in between. It’s available in different thicknesses, and you can cut it to fit around your dryer vent. Plus, it’s easy to install and can be held in place with tape or screws.

Fiberglass Batts

Fiberglass batts are also easy to install. You just need to cut them to size and fit them around the dryer vent.

The plus point of fiberglass is its resistance to mold and fire. So if you live in an area prone to wildfires, this insulation can help protect your home.

Mineral Wool

Mineral wool is made from spun fibers of rock. The insulation can come in the form of batts or loose fill. It’s also fire-resistant and can help to block out noise.

However, you should be careful when working with mineral wood. The material can be irritating to your lungs and skin if inhaled. Since it has tiny particles of stone and glass, it can also be sharp and cause cuts.


Cellulose is made from recycled paper products. It’s a good choice for insulation if you’re looking for something environmentally friendly. The material is also fire-resistant.

One downside to cellulose is that it can attract rodents and pests. If you live in an area with a lot of rodents, you might want to choose a different type of insulation.

Spray Foam

Spray foam is among the best options for around a dryer vent. It can be sprayed into place and will expand to fill any gaps.

The material is also very effective at blocking out air and moisture. Plus, it’s easy to install and can be used in difficult-to-reach areas.

Since it does not provide a food or breeding ground for pests, it’s also a good choice if you live in an area with rodents.

Can You Use Spray Foam to Insulate a Dryer Vent?

You might be wondering if you can use spray foam to insulate a dryer vent. The answer is yes, but there are a few things to consider before doing so.

First, it’s vital to ensure that the dryer vent is clean and free of any lint or other debris. If there’s any buildup in the vent, it could catch fire and cause a severe hazard.

Once you’ve ensured that the vent is clean, you can go ahead and apply the spray foam. Use closed-cell spray foam for the best results. It is designed to expand and fill any gaps or cracks, creating a tight seal that will help prevent heat loss.

However, it does not expand as much as open-celled foam, which is exactly what you need for the dryer vent. If the foam expands too much, it can crush the dryer vent and cause serious damage. Open-celled foam is also much more flammable than closed-cell foam, so it’s not the best option for this application.

Apply the foam evenly and smoothly, avoiding any gaps or voids. If you’re unsure how much to use, err on using more rather than less.

Once the foam is in place, allow it to dry for 24 hours before using the dryer. It will give the foam time to cure and create a strong seal.


The advantages of spray foam insulation are:

  • Deters moisture around the dryer vent, which prevents mold or mildew formation
  • Reduces noise from the dryer
  • Helps keep the dryer vent area clean and free of debris
  • Fills any gaps or cracks around the dryer vent, preventing heat loss


The disadvantages of spray foam insulation are:

  • Can crush the dryer vent if it expands too much
  • Is flammable (although this is less of a concern with closed-cell foam)
  • Has a high upfront cost

What’s The Best Insulation to Use Around a Dryer Vent?

Fiberglass is the most popular insulation material and is used in various applications, including around dryer vents. Fiberglass is an excellent insulator and has a high R-value, which means it resists heat transfer.

It’s also non-flammable and won’t settle or compress over time. While spray foam is a good option for most other places, its application around dryer vents can be tricky. If you apply too much or use a highly expanding formula, it can block the vent entirely. As a result, it can cause the dryer to overheat and become a fire hazard.

On the other hand, fiberglass insulation is easy to apply and won’t present any fire risks. It’s also one of the most affordable options on the market.

Lint can be a fire hazard in dryer vents. Therefore, it’s important to remove it. Use a flexible brush system that can be inserted into the vent to clean it. It is also known as a lint brush and is available at most hardware stores. 

Are There Any Other Ways to Weatherize the Dryer Vent?

Weatherizing the dryer vents help reduce utility bills as it ensures that the dryer is working efficiently. In addition, it prevents house fires, especially those caused by lint buildup in the vents.

Besides insulation, there are a few other ways to weatherize the dryer vent. Here are some of them.

Using Caulk

One way to weatherize a dryer vent is to use a special type of caulk that can withstand high temperatures. The caulk can be applied around the edges of the dryer vent opening to seal it off and prevent cold air from coming in.

Applying Tape

You can also apply a strip of tape around the edge of the dryer vent opening. However, don’t use regular ol’ duct tape, as it won’t be able to withstand the high temperatures of the dryer vent.

Instead, use a high-temperature tape designed to be used in such situations. You can find this type of tape at most hardware stores.

Adding a Cover

If you’re serious about weatherizing the dryer vent, you can add a cover. Keep in mind, though, that the cover will need to be removed each time you use the dryer vent.

A cover can be made of various materials, such as metal or plastic. Just make sure it can bear high temps.


Evan has decades of experience as a project manager for large-scale commercial renovation home-building projects throughout the US. Currently, Evan runs a successful construction management company in Virginia.

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