Cold Draft Under Baseboard | Reasons and Solutions

It’s common for people to relax and enjoy a cool breeze when the weather is nice outside. However, when you’re indoors, that cool breeze is more of a nuisance than anything, and if t’s coming from under your baseboards, it is indicative of some issues with your home.

If you’re feeling a cold draft from your baseboards there are three factors contributing to the problem. Luckily, all can be addressed, although the ease of the remedies differs. We’ll be covering what those problems are so you can determine what’s most likely causing the draft in your home, and how you can fix it.

Three factors contribute to baseboard drafts: uninsulated walls, baseboard gaps, and ceiling or window cracks. Air enters uninsulated walls and is pulled from under the baseboard by a vacuum effect created as air leaves through window and ceiling cracks. Insulating and filling cracks and gaps is the solution.

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3 Contributing Factors to Baseboard Drafts

Houses are always “breathing” by circulating air into and out of themselves. If there are cracks allowing air to travel where it shouldn’t be able to, a draft could be created in your home. These three areas are the most likely culprits, and they act together:

Uninsulated walls.
Gaps in or between baseboards.
Cracks along edges of building features like doors and windows.

1. Uninsulated Walls

If your walls aren’t insulated well, the air from outside has a significantly easier time settling into them. This gives it access to places like your baseboards, where tiny gaps, which are normal, can create a draft by allowing the air to be pulled inside the home.

Even if your walls are insulated, the type and age of the insulation may mean that it is no longer functioning properly and there are gaps through which air can easily pass.

While many types of insulation can last for over 80 years, harsh weather conditions, pest infestations, and water damage could all contribute to insulation deteriorating more quickly.

To determine if the insulation in your home is adequate, you can remove an electrical outlet (make sure to turn the power to the outlet off using your breaker, first!) and take a peek inside.

If you are unsure if your insulation is adequate, you might choose to get a professional opinion.

Solutions

If it does appear that poor wall insulation is contributing to your baseboard draft, it is probably in your best interest to employ the services of a professional insulation contractor to insulate your walls for you.

While DIY-ing home projects can often save you money, insulating an existing wall is a difficult task to do on your own because there are so many factors to consider.

For example, what type of insulation is best for your home? Would it be better to access the wall’s interior through the inside or outside, and how do you do that without causing unnecessary damage? How do you insert the insulation evenly, and how do you repair the walls afterward without leaving a trace?

If you plan for all these things it’s certainly a job you could do yourself, but it might be worth the hassle to hire a professional.

2. Gaps and Cracks in Baseboards

Of course, for a draft to blow from under your baseboards there needs to be a place for the air in the walls to enter the room. Gaps and cracks in the baseboards provide these inroads.

Even if your walls are well insulated, air will still fill any remaining space inside them, which can then be pulled through any crevices in your baseboards.

If your baseboards have cracks in them, or if they were installed with gapping between the boards, these are spaces that can allow outside air to enter the home. The area between the baseboard and the floor is another spot that may not have been sealed correctly.

If you live in an older home, there is once again the possibility that the materials that were originally used to seal your baseboards have “gone bad” and need to be replaced.

Solutions

Luckily, sealing your baseboards is a pretty easy job to do yourself.

Firstly, if there is old caulk, you will need to remove it. A putty knife _{^{(amazon link)}} can help you to slice through and peel away old material.

After removing any old caulk, you’ll want to select a latex-based caulk _{^{(amazon link)}}. Latex-based caulks take paint very well. This makes them ideal for baseboards, which are likely to be painted over in the future.

Using a caulking gun, you can apply caulk along the edges of your baseboards. After filling each section of your baseboard, use a wet finger to even out the bead of caulk and wipe away excess.

If you’re sealing cracks in or between the baseboards, you can still use caulk as filler. After applying it to the cracks, use a putty knife to scrape away excess. Then, use a wet rag to wipe away additional residue before it dries.

I have a whole article dedicated to the easiest and most effective ways to seal gaps between your baseboard and floor.

3. Reasons Air Is Pulled Into Room

Much like the gaps between your baseboards themselves, there are several other places around your home where small crevices could be allowing air to flow where it isn’t meant to.

Ceiling Cracks and Fixture Gaps

If there are cracks in your ceiling, you may want to take a look at them. This may seem counterintuitive if you’re feeling the draft from the floor, but these cracks can be contributing to the issue.

While ceiling cracks don’t usually indicate a major structural problem, they can allow air to escape your home through the attic or crawl spaces between floors. This loss of air will cause your home to compensate by pulling air into itself wherever possible—like through the baseboards.

If your ceiling crack is ⅛” thick or more, you should look into having your home assessed just to ensure that there isn’t a structural problem.

If your ceiling has no cracks but instead there is a gap where a light fixture does not completely cover a hole, this can also allow air to exit the home unnecessarily.

Solutions

If it has been determined that your ceiling cracks are not the result of a structural issue, then you can proceed with filling and repairing the cracks to prevent the escape of air.

Ceiling cracks can often be fixed with mesh repair tape _{^{(amazon link)}} and joint compound _{^{(amazon link)}}. This video will guide you on how to fix the problem yourself.

If the problem is a gap where your light fixture is installed, this can be fixed by removing the light fixture, then using a plaster or drywall compound to fill in the edges of the hole.

Once this compound is dry, you can sand it to be flush with the rest of the ceiling, paint if necessary, and reinstall the light fixture.

Leaky Windows

Leaky windows could serve as either an entry or an exit for air.

This means that just like openings in the ceiling, air escaping through leaky windows could be causing a draft by forcing air to be sucked into the room through other crevices.

Alternatively, air could be being pulled into your home through the windows and adding to the draft itself.

Handyman in goggles holding clipboard and checking window

Much like with your baseboards, a leaky window is likely caused by an old or poorly done sealing job, though this could be on the interior or exterior of the frame, and on either the inside or outside of the wall.

Solutions

Assess your windows to determine where an air leak might be coming from. You can probably do this visually with a close inspection, but you may also be able to feel along the edges to see if you notice any airflow or deteriorating caulk or weatherstripping.

If you have identified an issue with the seal around your windows, you can treat the problem here like you would treat poorly sealed baseboards.

Remove any old caulk or sealant, clean the area, and reapply caulk.

If you are sealing the interior, you will probably want to use a latex-based caulk. If you are sealing the exterior, you should probably opt to use an outdoor silicone-based caulk _{^{(amazon link)}}.

If there are any particularly large gaps you are filling, you may want to stuff a foam backer rod into the crack before caulking over it.

Cracks Around Doors

Doors are yet another common area where gaps are common. Just like leaky windows, unsealed cracks around your door can be intakes or exits for the air in your home.

As with windows, these gaps could exist on either the inner or outer edge of the frame, on the inside or outside of the building. It is also possible that the gap between your door and the floor is not properly sealed.

Carpenter fix jamb in doorway using a cordless drill electric screwdriver — Woodworker screwed the jamb in doorway using a cordless drill electric screwdriver, close-up.

While there are several possibilities for the location of a leak around your door, none of them should be too difficult to correct.

Solutions

Since doorframes are much like window frames, you will want to seal them in the same manner. Remove old caulk, then use latex caulk to seal indoor cracks, and outdoor silicone caulk on any outdoor cracks.

You should also check the bottom door seal for all your entry doors. If you find that the seal does not fully cover the gap, or has otherwise gone bad, you will need to replace it.

Replacing a bottom seal is often as simple as removing the screws (if there are any) and pulling or sliding the seal off. You will then place a new bottom seal on it. If it is too long for your door, you will need to mark it and cut it to size before placing it back on.

After sliding the new door seal onto your door, you can screw it into place.