3 Best Caulk Products for Air Sealing Your Home

Best Caulk for Air Sealing

Air sealing is one of the most effective ways to keep cool or warm air in your home throughout the year. It’s also an effective way to keep bugs and water runoff out.

Regarding air sealing, caulk is one of the most popular ways to do it. But what differentiates caulk from other strategies? And which caulk products should you get to air seal your home?

In this article, we’ll look at the three best caulk for air sealing and how they can improve your home.


Best Caulk for Air Sealing

Our picks for the best caulk for air sealing are:

There are three types of caulk that’s best suited for air sealing: latex, expandable foam, and butyl-rubber. Let’s take a look at the best product for each of these categories to find the best caulk for you.

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Dap Alex Painter’s Acrylic Latex Caulk

Best Latex Caulk for Air Sealing

When it comes to caulking, latex caulk is a popular choice because it’s versatile and easy to use. Acrylic latex caulk is perfect for filling gaps in drywall, wood, and masonry and can also be used for crown molding and baseboards.

One of the best options on the market is the DAP Alex Painter’s Acrylic Latex Caulk. This caulk is known for its excellent adhesion, the quick drying time of 2 hours, and long-lasting performance of up to 10 to 15 years. It’s ideal for setting door frames and sealing subfloors at the bottom of a door frame.

Using this caulk, you can quickly and easily fill any gaps between drywall, doors, or windows, providing an airtight seal that can save you energy costs and prevent moisture from seeping through.

When selecting the right caulk for your home improvement project, it’s essential to consider factors such as adhesion, drying time, and longevity. The DAP Alex Painter’s Acrylic Latex Caulk checks all the boxes and provides a reliable and long-lasting solution for your caulking needs.

Expandable Foam

DAPtex Plus Foam

Best Expandable Foam Caulk for Air Sealin

As attic insulation and ventilation experts, we can speak from first-hand experience: expandable foam caulk is essential for sealing up gaps and holes around your home.

This type of caulk can expand and fill up larger spaces using polyurethane spray foam insulation, making it perfect for areas around leaky electrical outlets, pipes, and window jambs.

The best expandable foam caulk on the market based on our testing is DAPtex Plus Foam. It is one of the most affordable options and offers exceptional sealing properties that can keep pests out of your home indefinitely.

One of the best things about DAPtex Plus Foam is that it’s paintable, making it easy to match your home’s decor. Additionally, this foam caulk can help dampen the sound, providing a little extra soundproofing inside your home.

Whether you need to seal gaps around your home’s exterior or interior, the DAPtex Plus Foam is a reliable and easy-to-use solution that can help keep your home energy-efficient and pest-free for years.


Flex Shot Rubber Adhesive Sealant Caulk

Best Rubber Caulk for Air Sealing

Caulk is a versatile tool that can be used both indoors and outdoors. When it comes to outdoor projects, butyl-rubber caulk is an excellent choice for sealing up gaps and holes in materials such as aluminum, metal, concrete, mortar, plastics, or rubber.

One of the best butyl-rubber caulk products on the market is the Flex Shot Rubber Adhesive Sealant Caulk. It is affordable and reliable, making it an excellent choice for home improvement projects where small holes may leak air into the home.

This caulk can expand and fill larger cracks and holes, making it an excellent choice for outdoor projects. Additionally, the Flex Shot comes with its own tube, meaning you don’t need a caulk gun to apply it, making it convenient and easy to use.

Whether you need to seal up gaps in your roof, windows, or siding, the Flex Shot Rubber Adhesive Sealant Caulk is an excellent choice for all outdoor caulk needs.

Why You Should Air Seal

But why should you even bother air sealing? If you have proper insulation and ventilation installed, isn’t that enough?

Not necessarily. Think of your house like a boat. If you have a dozen small holes, the water will add up, and your boat will sink.

Similarly, your home might have proper insulation or ventilation installed, but small pockets of air will leak out all that cold or warm air your HVAC system is producing. This means wasted energy and higher utility costs.

Research shows that air leaks in your home can add up to one-third of your home’s total energy loss throughout the year. You’ll save a tremendous amount of money by air-sealing your home, especially if you combine that with other insulation measures. For more information on cost savings, check out our guide: Is Air Sealing the Attic Worth It?

Whether it’s your attic, windows, electrical outlets, fireplaces, or floor holes, proper air sealing will help you considerably reduce your energy costs.

Caulk vs. Sealants

Caulk and sealants are terms often used interchangeably.

While they share some similarities, we should address a few differences between these two products to make sure everything is clear.

Caulk describes waterproof material that fills and seals joints between building materials. They’re typically made out of flexible polymers like latex or rubber.

Caulk can expand with temperature changes and absorb vibrations. Caulk can’t crack, so it’s often used to connect materials on two different planes.

When compared to sealants, the biggest difference is elasticity. When dry, caulk is much more rigid than sealants, which are more suited for filling spaces prone to expansion or contraction.

When choosing between the two, consider the amount of stress in the sealed area.

How to Seal Air Leaks With Caulk

Are you interested in air-sealing your home with caulk? Great!

Air sealing is a relatively inexpensive and easy DIY project you can complete quickly if you have the right equipment and know the proper steps. Let’s go over some of that here.

Before You Start…

Make sure you have everything you need to get this project done. Here’s a basic shopping list for a successful air sealing project:

  • Caulk
  • Caulk gun if the caulk you purchase doesn’t come with a nozzle
  • Putty knife or large screwdriver to remove old caulk
  • Paper towels and rags for cleanup

Step-By-Step on Air Sealing

Start by removing any old caulk in the area you want to seal using your knife or screwdriver. Ensure it’s nice and dry, so you don’t caulk in moisture.

If you’re using a caulking gun, cut the tip of the cartridge of the caulk at a 45-degree angle and insert the tube in the gun. Take time to do a “test caulking” on a newspaper or paper towel. This will give you a good sense of what to expect, so you don’t over-caulk a window or floor.

Hold the caulk gun or nozzle at a 45-degree angle against the surface you’re trying to seal. Using a “pulling” motion, keep the angle as you slide the tube along the open joint while pulling the trigger. Try to keep a consistent stream as you go along.

Once you’ve made a nice line of caulk or filled a single spot, use your finger or a spoon/paintbrush to dampen the caulk into the filling. This will force it deeper into the spot and help it expand.

Clean up any excess caulk with a rag, and let it sit undisturbed for about a day. How long the drying process takes depends on your product and the humidity and air temperature.


Will caulking keep cold air out?

Yes, caulking can help keep cold air out of your home. Caulking is a sealing material applied around gaps and cracks in doors, windows, walls, and other areas where air can enter or escape your home. By sealing these gaps, caulking can help prevent cold air from entering your home and warm air from escaping, which can help improve your home’s energy efficiency and reduce your heating costs.

It’s important to note that while caulking can effectively reduce air leakage and improve energy efficiency, it’s not a substitute for proper insulation. If your home is poorly insulated, it may still be susceptible to cold air infiltration even if you’ve caulked all the gaps and cracks. Consider adding insulation to improve your home’s energy efficiency and keep cold air out.

Is silicone caulk airtight?

Silicone caulk is generally considered airtight, but its effectiveness in creating an airtight seal can depend on several factors, such as the quality of the caulk, the surface it is applied to, and the conditions under which it is applied.

Silicone caulk is a popular choice for sealing gaps and cracks because it is flexible, waterproof, and has excellent adhesion properties. It can be used on various surfaces, including glass, metal, plastic, and paint. Applying it correctly can create an airtight seal that helps prevent air infiltration and heat loss.

However, it’s important to note that no caulk can be completely airtight in all situations. Factors such as temperature changes, movement of the surfaces being sealed, and the age of the caulk can all affect its effectiveness over time. Additionally, some types of silicone caulk may shrink or crack over time, compromising their airtight seal.

In summary, silicone caulk can effectively create an airtight seal. Still, choosing a high-quality product, applying it properly, and monitoring it over time are essential to ensure its effectiveness.

Which is better latex or silicone caulk?

The choice between latex and silicone caulk depends on the specific application and the conditions to which the caulk will be exposed.

Latex caulk is a water-based product that is easy to apply, dries quickly, and can be painted over. It is typically less expensive than silicone caulk and can be used for various indoor applications, such as sealing gaps around windows, doors, baseboards, and trim. Latex caulk is best used for non-porous surfaces not exposed to high moisture levels or extreme temperature changes.

On the other hand, Silicone caulk is a more versatile product that can be used for indoor and outdoor applications. It is a waterproof product that can withstand exposure to moisture, extreme temperatures, and UV radiation. It also has excellent adhesion properties and remains flexible over time. This makes it ideal for sealing gaps around windows, doors, and other areas exposed to water, heat, or cold.

In summary, latex caulk is a good choice if you’re looking for a caulk that is easy to apply and will work for most indoor applications. However, if you need a caulk that will withstand exposure to moisture, extreme temperatures, and UV radiation, then silicone caulk is a better choice.


Air sealing has clear benefits, and choosing the right caulk is one of the most important steps to taking advantage of them. Use this article to find the right air sealing caulk and make your home more energy-efficient today!