The Fix Everyone Tries First (and Why It Fails)
Here's the pattern we see on almost every service call about drafts or water under a garage door: the homeowner noticed a gap, grabbed a tube of caulk or an old towel, and sealed it up themselves. It's an understandable move. Caulk is cheap, a towel is already in the garage, and both seem to stop the problem that same afternoon.
The trouble is neither one actually fixes anything. Caulk cracks the first time the door opens and closes a few dozen times, because it was never designed to flex with a moving part. A towel soaks up water and dust instead of blocking it, which means it stays damp against your slab, invites mold, and gives rodents and spiders a cozy place to nest once the weather cools. By the time most people call about a drafty garage, the real problem is a worn or missing bottom seal and brittle weatherstripping along the sides and top — and that's a part you can actually replace.
What a Worn Seal Is Really Costing You
A bottom seal and the companion weatherstripping around the sides and top of the door frame do three jobs: keep water out during winter rain, keep dust and wildfire smoke from sneaking in during our dry, dusty stretches, and keep pests from finding an easy entrance when outdoor temperatures drop. When that seal has flattened, cracked, or pulled loose from its track, you'll notice:
- Daylight visible under the closed door
- A line of dust or grit along the inside of the door after a windy day
- Water pooling just inside the threshold after rain
- Spiders, mice, or leaves collecting in the corners
None of that requires a full door replacement. It requires about an hour, a few tools, and a trip to a hardware store or supplier for the right seal.
Tools You'll Need
- Tape measure
- Utility knife
- Flathead screwdriver or small pry bar
- Replacement bottom seal matched to your track style (bulb-style T-seal or bead-style, depending on your door)
- Replacement weatherstripping for the side and top frame (often a separate strip)
- Mild soap and water or a household cleaner
- Work gloves
- A second person to help steady the door, if you're working with it partly open
Step-by-Step: Replacing a Bottom Seal
- Close the door and identify the track style. Most bottom seals sit in a routed channel on the underside of the door. Look at the shape of that channel — it's either a T-slot or a bead-style groove. Replacement seals are not universal, so bring a cut piece of the old seal with you when you shop, or measure the door's width and the channel shape.
- Clean the track and threshold first. Before you touch the new seal, scrape out old caulk, dirt, and debris from the channel and from the concrete threshold underneath. A seal installed over grit will never sit flush.
- Pull the old seal free. Most slide out of the track lengthwise. If it's brittle, it may come out in pieces — use the flathead screwdriver to work out any stubborn sections.
- Measure and cut the new seal about an inch longer than the door width, so you have a little slack to work with.
- Feed the new seal into the track from one end, sliding it through the full length. This is easier with a helper holding the far end steady.
- Trim the ends flush once it's fully seated, using the utility knife.
- Open and close the door a few times to check that the seal compresses evenly against the threshold with no gaps at the corners.
Step-by-Step: Side and Top Weatherstripping
- Peel off the old strip, which is usually tacked or stapled to the frame.
- Clean the frame surface so the adhesive-backed or tacked replacement strip bonds properly.
- Press the new strip into place, starting at one corner and working across, checking that it meets the bottom seal with no visible gap at the corners — that's the spot where dust and water sneak in most often.
What's DIY and What Needs a Technician
Replacing a bottom seal or side weatherstripping on a door that's sitting closed and accessible is a reasonable homeowner project. Where we draw the line:
- Call a technician if the track itself is bent, rusted through, or detached from the door panel — a new seal won't seat properly on a damaged track.
- Call a technician if replacing the seal means removing panels, disassembling the bottom section, or working near the door while it's held open by the spring system. That's tension you don't want to manage without the right bars and experience.
- Call a technician if water intrusion has been going on long enough that you suspect rot in the bottom panel or rust on the tracks and rollers — that's a repair job, not a seal swap.
When to Call Clovis Garage Door Service
If your bottom seal keeps failing within a season, if the track it sits in is damaged, or if you're seeing water intrusion alongside other issues like a door that feels off-balance or sticks partway, it's worth having us take a look. Our Garage Door Maintenance visits include checking seals, tracks, and hardware together so you're not chasing one symptom at a time, and if the frame or track itself needs attention, our Garage Door Repair service handles that safely, tension and all.
Give Clovis Garage Door Service a call before the winter rain starts pooling at your threshold — we serve Clovis, Fresno, Sanger, Madera, Selma, Reedley, Kerman, and Kingsburg, and we're happy to get your door sealed up right.