Photo image of light switch plate gasket for air sealing

Air sealing your home can be a low-cost way to save money on your energy bills while also increasing the efficiency of your home.

No matter where you live or how old your home is, there are likely ways to improve the air sealing of your home without breaking the bank or needing to hire a professional.

In this article, we will break down five budget home air sealing products that will ultimately save you money. Not only will improving the air sealing on your home have an immediate effect on your electric bill, it will also continue providing savings long-term. These products include:

  • Caulk
  • Expandable Foam
  • Weather Stripping
  • Ductwork Sealing
  • Outlet and Switch Sealers

Some of the air sealing products and fixes are maintenance that may need to be checked on every few years, even on newer homes. Think of it as doing a check-up on the house. Even for new homes, there will be some wear and tear on the exterior of the house over time.

A lot of people think if they have good insulation in their home, it is efficient. But you can have the best insulation and still have air leaks, which actually account for ⅓ of all energy loss annually. This is significant and can have a serious impact on your energy bill.

We also built a pretty slick home air sealing calculator that uses your own utility bill (and other factors) to show a wealth of data on the benefits of air sealing. You can find that here.

First Steps in DIY Home Air Sealing to Save Money

The first step in DIY air sealing is identifying the air leaks. This will determine what products you will need to air seal your home. There are a couple of simple steps that can be taken to pinpoint where fixes will need to happen.

Interior and Exterior Inspection

The simplest way to identify air leaks is to do a visual inspection of the interior and exterior of your home. It is important to look from floor to ceiling and everywhere in between. Some key locations include anywhere where there is a hole in the wall or some form of connection from the exterior to the interior of the house. This includes windows, doors, outlets, lighting fixtures, air conditioner units, and any utilities that come into the home aboveground.

On the exterior of the house, look in the same locations but also check for any holes or cracks in the facade. If you have stone or brick these will likely be more obvious than with other materials.

When inspecting windows, be sure to check both the framing around the windows and the glass itself. On some styles of windows, there can be cracks or gaps that develop near where the glass connects to its frame.

A tip for easier inspection is to use a bright light. Have one person take the light to the exterior of the home with one person on the interior. Move it around a door, window or any other area that you are testing; if you can see the light, then there is a crack or hole that needs to be fixed.

For areas that are hard to have someone on either side of, you can use a stick of incense or a candle. If the flame flickers or the smoke is clearly being blown, then there is an air leak somewhere.

Confirm These Things

You will also want to do a quick visual check to confirm a couple of things. This is pretty simple to do and could identify major leakage points. First, check to make sure that all bathroom and kitchen vents have a flap on the exterior. Without a flap, there will simply be free-flow air coming into and escaping from your house. A flap is a simple mechanism that allows the necessary air out of the home but prevents unwanted air from entering. You should also check for a flap on the dryer vent.

Second, if you have a chimney, check to make sure that you not only have a cover but also that it is in proper working order. Without a cover, your chimney will act similar to the vents, a free-for-all for escaping air. (Additionally, a chimney without a cover is a potential access point for pests and animals to enter or build nests in the home.)

If the vents or chimney do not have a flap or cover, this needs to be fixed. It can be done either by you or a professional.

Conduct a Blower Door Test

A blower door test is a way to identify air leakage that is typically performed by a professional. These tests pinpoint exactly what the air leakage in the home is, where it is coming from, and how much energy is being lost.

If you are concerned about the air leakage in your home or want exact answers, it can be very beneficial to do a blower door test. You could also try some of the DIY solutions and, if drafts or air leakage still appear to be a problem, bring in a professional to help solve it.

Either way, none of the work you do to seal the house will be wasted. Air sealing can only help. So even if you just find a bunch of little cracks or holes, sealing them will still have a positive impact on the energy efficiency of your home. In some cases, the culprit behind air leakage can be hard to identify and a professional may need to be called in to perform this test.

Home Air Sealing Products


Caulk is one of the easiest and most cost-effective ways to air seal your home. This can be used around windows or doors. It is also great for any small interior or exterior cracks or holes in the home. It is important to note that caulk is meant for small holes or cracks.

Sealing the opening around an air register is just one of many uses for caulk.

When looking at different caulks, an acrylic latex caulk is your best option. It can last for up to 15 years and can be used on everything from wood to masonry. It adheres well to most materials so it can be used throughout your home, interior or exterior, on a variety of surfaces.

A tube of caulk should not run you more than $10 and most are under $5. If you are going to do any single task or air sealing fix, caulking should be at or near the top of your list. Even though the holes you are filling with caulk will be small, it can have a significant impact if there are multiple holes or cracks throughout the house.

Caulk comes in different colors as well as clear, so it is easy to achieve a professional finish. In addition to buying the tube of caulk, you will also need a caulk gun. This helps push the caulk out of the tube. There is an incredibly wide range of caulk guns on the market. Some of them cost hundreds of dollars, but those are professional-level tools. For home DIY and air sealing, a caulk gun should cost no more than $15.

If you notice bigger areas that might need to be sealed, an expanding foam is more appropriate. The tip of the caulk bottle is a pretty good guide. If the crack or hole is significantly wider than the tip of the caulk tube, then you probably need to use expanding foam.

Expanding Foam

Expanding foam is the next step up from caulk. This is for bigger holes or cracks. Expanding foam does not have the same finished or clear look that caulk has, so use it more for the exterior or unfinished parts of your home like an attic or basement.

There are some foams that you are able to paint over, so if you have to use expanding foam around a leaky outlet or lighting fixture or around windows and doors on the interior, look for expanding foam that can be painted over.

Similar to caulk, a can of expanding foam should be under $10 to purchase. The foam comes in an aerosol can so be sure to store it properly after use. Additionally, read all safety and usage instructions to ensure proper use of the material.

An added bonus of expanding foam, and air sealing in general, is that it will also help keep pests out of your home. Any gap that is large enough to need foam is big enough for pests to enter your home. The expanding foam will also seal off access to all pests!


For areas that cannot be completely sealed shut (like the bottom or top of doors or moving parts of windows), weatherstripping is a great option. It is attached to the door, window, or other area and provides a seal when the element is shut or not being used.

Closeup of the corner of a window showing the weather stripping
Weather stripping keeps air from seeping in around windows and doors.

This is usually a piece of silicone, aluminum, vinyl, foam, or other similar material that hangs over the edge of the door and touches the floor, providing a temporary seal.

While weather stripping isn’t as effective as expandable foam or caulk, it doesn’t serve the same purpose. Weatherstripping is meant to minimize airflow while still allowing movement for the item it is attached to.

The Dollar Test

One way to determine if your door or window needs weatherstripping is to take a piece of paper or a dollar. Set it at the base of the door and then close the door. If you can pull out the paper, then there is too big of a gap between the bottom of the door and the door itself. The same test can be done for windows and the other sides of the door.

The installation process varies depending on the weather stripping chosen. Some foam stripping comes in a roll with an adhesive on the back. You can simply stick the weather stripping to the desired area. Other options may need a bit more installation that may require a hammer, screwdriver, or drill. They are still fairly easy to install and can be done as a DIY project.

Because there are so many materials that weatherstripping is made of, you can definitely shop around to find one that matches or complements the door or window that you are installing it on. There is a range of colors offered including brown, black, and white.

Ductwork Sealing

Your ductwork is literally the avenue by which heated or cooled air is distributed to the rest of your house. Having a leak or crack in the ductwork can cause a significant amount of air leakage over time. This is one of the tougher DIY projects to complete, but it is still possible.

There are a couple of issues to look for when inspecting your ductwork. The first is to look at the connections between pieces of ductwork. These are weak points and are the most likely spots for leaks to occur. Look out for holes or cracks in the ductwork as well.

After identifying potential problem areas, there are a few steps you can take to fix the air leakage. The first is to use aluminum duct tape. The duct tape comes in a variety of widths and lengths that you can choose from based on what you need it for. Aluminum duct tape comes in rolls between 10 and 50 yards. It can cost anywhere from $4 for a thin width at a short length to $22 for a thicker width and more length.

The aluminum duct tape can be used to seal just about anything in the ductwork, from loose connections to small leaks or holes. After using the aluminum duct tape, use ductwork mastic. This seals any seams from the duct tape and gives some extra strength to make sure the air leakage points stay completely sealed.

If you live in a location with extreme hot or cold weather, where heating or air conditioning is used for a significant portion of the year, it is advised to install ductwork insulation as well. The insulation prevents the heat or cold itself from escaping through heat transfer. If hot or cold air is flowing through your ducts, the aluminum ducts will also get warm or cold which will, in turn, be transferred to the air.

Ductwork insulation minimizes heat (or cold) loss from the ducts. This is a bit more expensive and could cost several hundred dollars. However, if you do not currently have insulated ducts and choose to insulate them, you should see an immediate and sustained decrease in energy usage and costs.

Outlet and Switch Sealers

Photo image of light switch plate gasket for air sealing
Sealing the light switch plates in our first Attainable Home. Notice how the same seal can be applied to light switches or outlet plates.

This may seem like a small fix, but doing several small fixes can go a long way toward energy efficiency. If you notice air leakage at outlet or light switch points, you can get foam sealers to prevent excess leakage.

They are quite reasonably priced, typically around $20 for a pack of 50 or more. Most foam gaskets for outlets and switches have an adhesive on them and can simply be placed behind the plate. The gaskets or sealers prevent air leakage around the outlet or switch.

Similar gaskets can also be purchased to help seal off water lines, waste plumbing, and dryer vents–all areas that can contribute to the overall air leakage in your home. In addition to the sealers themselves, you will also need a screwdriver to take the outlet or light switch plates off of the wall.

Our Own Net-Zero Home and The Journey of Air Sealing

For our first net-zero home renovation completed in 2020, we ended increasing the building envelope tightness by 44%. Said in another way, we air sealed the house up by another 44%. Every house is different, but we got a huge impact by:

  • Sealing up all openings in the drywall
  • Using clear silicone caulk between all baseboards and the flooring – this is huge as air seeps in through your walls.
  • New Energy Star double pane hurricane impact windows and doors
  • Caulk everywhere there was a gap
  • Spray foam can insulation where possible
  • Outlet cover insulation behind the wall plates
  • And basically anything else where there was any sign of an air gap in the house

This actually led to a bigger efficiency savings (money and energy) than we thought, and it turned out that we oversized the solar system a little too much. But that just speaks to the power of air sealing before you do anything else when going for energy efficiency and money savings on the utility bills.


Taking on air-sealing as a DIY project can be similar to a house-sized puzzle. You will need to identify the air leakage points and appropriately seal them off. It can seem overwhelming, but if you are methodical and organized about finding the leakage points, marking them, and then performing the fixes, it should be a fairly smooth and easy process.

Some fixes are harder than others, and you may choose to perform some yourself and hire a professional for others. In all cases, just make sure you are taking safety precautions and using all of the materials as they were intended!

Performing air sealing can have a significant impact on your energy efficiency and energy bills. And, it will be a sustainable change, not just a one-time dip in your utility bill. The effects of air sealing will be most noticeable in hot or cold weather when the temperature outside the house is significantly different from the temperature inside the home.

Home air sealing requires continued maintenance. It is not something that needs to be inspected monthly or even annually, but it isn’t a bad idea to give things a look over every couple of years. If at any point you notice a significant draft or temperature difference in your home, you may want to consider performing a visual inspection again.

After you have performed the initial air sealing, you likely won’t have to do a serious visual inspection or blower door test for a long time. However, it is quick and easy to do a look over of the exterior of the house when gardening or performing other yard work. If you see a new air leakage point, no matter how small, you already have the skills and materials to fix it quickly and efficiently. 

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