If you've noticed a draft or seen daylight peeking through the edges of your door, you really need to seal garage door sides from inside to keep things comfortable. It's one of those weekend tasks that usually gets pushed to the bottom of the list, but honestly, once you do it, you'll wonder why you waited so long. A drafty garage isn't just cold in the winter; it's a gateway for dust, spiders, and those annoying leaves that somehow find their way into every corner.
Most people think they need to hire a professional or buy a whole new door to fix the gaps, but that's rarely the case. In most garages, the door doesn't sit perfectly flush against the frame. Over time, the house settles, the tracks shift slightly, or the original seals just dry out and crack. By focusing on the interior side of the door, you can create a secondary barrier that works wonders for your energy bills and your sanity.
Why You Should Focus on the Inside
Usually, garage door weatherstripping is installed on the outside of the door jamb. While that's the first line of defense, it's not always perfect. The outside seals are constantly exposed to UV rays, rain, and freezing temperatures, which means they wear down faster than you'd think. When you seal garage door sides from inside, you're essentially adding a backup layer that stays protected from the elements.
Think about it this way: the outside seal pushes against the door from the front, but there's often a little "wiggle room" in the tracks. By adding a seal on the inside, you're sandwiching that gap. This is especially helpful if you use your garage as a workshop, a gym, or even just a place to keep your laundry. It makes the space feel like an actual room rather than just a concrete box with a giant moving wall.
Finding the Gaps with the Light Test
Before you run to the hardware store, you need to know exactly where the air is getting in. The easiest way to do this is what I call the "light test." It's pretty simple: head into the garage during the day, close the door, and turn off all the lights. Give your eyes a minute to adjust.
Anywhere you see white light shining through is a spot where air, water, and bugs can get in. Pay close attention to the vertical sides. You might see a thin sliver of light running the whole way up, or maybe just a few spots where the door seems to bow away from the wall. These are your target areas. If you can see the neighbor's house through the crack, it's definitely time to get to work.
Choosing the Right Seal for the Job
You've got a few options when it's time to actually buy materials. You don't need anything fancy, but you want something that's going to last more than one season.
Brush Seals
These are my personal favorite for the interior. Brush seals consist of a metal or plastic track with thousands of tiny, flexible bristles. The beauty of these is that they don't create much friction. When the garage door moves up and down, the bristles just glide along the surface. They're excellent at stopping drafts while still letting the door move freely.
Rubber or Vinyl Flap Seals
These are very common and usually pretty affordable. They're basically a strip of flexible material that you screw or nail into the door jamb. When the door closes, it presses against the flap to create a seal. They work great, though they can sometimes get a bit stiff in really cold weather.
Foam Tape
This is the "budget" option. It's easy because it's peel-and-stick, but I'll be honest with you—it's usually a temporary fix. In a garage, the door is constantly moving, and that friction tends to peel the foam off after a few months. If you're in a pinch, it's fine, but for a long-term solution, stick with the brush or vinyl.
How to Install the Seals Correctly
Once you've got your materials, it's time to get your hands dirty. Don't worry, it's not a complicated job. You'll just need a tape measure, a utility knife (or a small hacksaw if you're using metal-backed brush seals), and a drill or screwdriver.
First, clean the area thoroughly. I can't stress this enough. Garages are dusty places. If you're using any kind of adhesive, it won't stick to a layer of grime. Even if you're screwing the seals in, it's much nicer to work on a clean surface. Wipe down the inner door jambs with a damp rag and maybe a little bit of degreaser if things are really oily.
Measure the height of your door from the floor to the top header. You'll want to cut your side seals to this exact length. When you're ready to mount them, close the garage door completely. This is important because you want to position the seal so it's just touching the door. You don't want it so tight that the door struggles to open, but you don't want a gap either.
If you're using the screw-in type, start at the top and work your way down. Don't tighten the screws all the way until you've checked the fit. Once the seal is in place, pull the emergency release cord on your opener and try moving the door by hand. It should feel smooth. If you feel it catching or if the motor sounds like it's straining when you plug it back in, you might have the seal pressed too hard against the door. Just back it off a hair and you'll be good to go.
Don't Forget the Corners
A common mistake people make when they seal garage door sides from inside is ignoring the very bottom and the very top corners. These are the "triple points" where the side seal meets the floor seal or the top header seal.
Often, there's a little 1-inch gap right at the bottom corner where the side seal ends. You can usually fill this with a small piece of scrap rubber or even a bit of silicone caulk. It might seem minor, but that little corner is exactly where mice like to squeeze through. If a mouse can fit its head through a gap, its whole body is coming inside, so keep those corners tight.
Maintenance and Upkeep
Once the seals are installed, you aren't quite finished for life. It's a good idea to check them once a year, usually right before the weather gets nasty. Over time, the door might shift, or the seals might collect a bit of gunk.
If you have vinyl seals, you can wipe them down with a little bit of silicone lubricant to keep them from getting brittle. If you have brush seals, just run a vacuum over them or use a stiff brush to knock out any trapped cobwebs or dust. It only takes five minutes, but it keeps the seal working perfectly.
The Added Benefits of a Sealed Garage
Beyond just the temperature, you'll notice a big difference in noise. Garage doors are basically big metal drums that vibrate. When you seal garage door sides from inside, you're adding a bit of dampening to the system. The door won't rattle as much when the wind blows, and you'll hear less of the street noise from outside.
It also helps keep your garage cleaner. If you're tired of sweeping out piles of dust and dead bugs every weekend, these seals are your best friend. It turns the garage from a semi-outdoor space into a legitimate part of your home's envelope.
Final Thoughts
Sealing the sides of your door from the inside is a low-cost, high-reward DIY project. It doesn't require any specialized skills, and you can get it done in an afternoon. Whether you're trying to keep the heat in, the bugs out, or just want a quieter home, taking the time to seal garage door sides from inside is always worth the effort. Grab your tape measure, check for those light gaps, and get that garage sealed up tight!