Sealing the Gaps Around a Garage Door: Scorpions, Dust and Cedar Pollen
A closed garage door is not a sealed one. In Round Rock, what gets through the gaps tends to have legs or come in on a January wind.
By Garage Door Care of Round Rock · · 6 minute read
Five Places a Garage Door Leaks
A garage door leaks in five places: along the bottom seal, down both sides at the stop molding, across the top of the opening, between the door sections, and where the slab meets the driveway. The bottom seal and the side stops account for most of it. Each has its own replacement part, usually fitted in under an hour, and the check that finds them takes ten minutes. If the door itself is sitting crooked, the gaps are a symptom and the fix is alignment work first.
In Round Rock the gaps matter for three reasons. Striped bark scorpions are a fact of life on the edges of this city, and they come in through the same openings as the dust. Mountain cedar pollen arrives every winter on dry cold fronts. And on the east side, clay moves the slab enough to open a wedge under one corner that was not there when the house was built.
The Ten-Minute Daylight Test
Pick a sunny afternoon. Close the garage door, turn off the garage lights, and give your eyes a minute to adjust. Every place light shows is a place air, dust and insects can move.
The bottom edge
3 minutesKneel and look along the floor from one side to the other. A thin even line is a worn seal. A wedge at one end is a door or slab that is no longer level.
Both sides
3 minutesLook up each jamb where the door meets the stop molding. Light here means the flexible flap has hardened, split or pulled away.
The top
2 minutesA stepladder and a look along the header. Many doors never had a top seal fitted at all.
Between sections
2 minutesLight at the joints between panels on a steel door usually means worn hinges or a door that is out of adjustment rather than a missing seal.
Scorpions, Dust and Pollen, by Season
Scorpions. The striped bark scorpion is the one Round Rock homeowners find in garages, usually near stored boxes and along the base of the walls. Texas A&M AgriLife's guidance on striped bark scorpions puts the emphasis on two things: removing the places they shelter near the house, like stacked firewood, rock and brick piles and landscape timbers, and making sure the weather stripping around doors actually seals. A garage door with a worn bottom seal is the biggest door on the house with the worst weather stripping.
Cedar pollen. The Texas A&M Forest Service dates the mountain cedar season from mid-December to early March, with the peak in mid-January, and notes that the pollen blows for miles and is worst west of I-35. The dry cold fronts that release it also drive it under a garage door and into the house through the connecting door. If anyone in the house suffers through January, the garage seals are part of the answer.
Dust and water. Summer thunderstorms drive rain sideways under a worn seal, and the dry months between them fill the garage with the fine grit that ends up in the opener rail and the roller bearings.
Each Gap Has Its Own Part
| Where the gap is | What comes through | The fix | Rough cost fitted |
|---|---|---|---|
| Along the bottom, even line | Dust, water, insects | New bottom seal in the existing retainer | $90 to $220 |
| Along the bottom, wedge at one end | Everything, plus the door is working unevenly | Door leveled and tracks plumbed, then the seal | $135 to $300 plus the seal |
| Down the sides | Pollen, dust, light | Vinyl stop molding with a flexible flap, both jambs | $150 to $350 |
| Across the top | Pollen, insects, wasps | Top seal or stop molding across the header | $60 to $150 |
| Between sections | Drafts, light | Hinges tightened or replaced, door adjusted | Part of a tune-up, $49 to $140 |
| Slab to driveway | Water, scorpions along the slab edge | Threshold seal bonded to the floor | $60 to $150 |
Rough installed ranges. Doors wider than 16 feet, retainers that need replacing and seals special-ordered for older doors cost more. You hear the exact figure before any work starts.
Picking the Right Bottom Seal
Bottom seals are not universal. They slide into an aluminum or steel retainer along the bottom edge of the door, and the retainer decides the shape. The three common profiles are a T-style with two beads that slide into the retainer, a J-type that hooks in, and a bulb seal that closes a larger gap. Take a small piece of the old seal to the store, or read the brand and model off the end stile label, and you will get the right one.
Where the slab has settled unevenly, a taller bulb seal helps, up to a point. Past about half an inch the seal is hiding a problem rather than solving it, and the door will wear through it within a season. On the east side of the city that is often the clay at work; our guide to how Round Rock's soil moves garage doors explains how to tell, and the USDA Web Soil Survey shows what is under your lot.
One part to leave alone. The bottom brackets, at the lowest corners of the door, hold the lift cables and carry the full spring tension. Replacing the seal does not require touching them. If a retainer is so rusted that the seal will not slide in, that is a job for a technician.
Three Habits That Keep Scorpions Out of the Garage
- Store boxes on shelves off the floor, in plastic bins rather than cardboard, which gives scorpions nothing to shelter in
- Keep firewood, stone edging and yard debris away from the garage walls and the driveway edge
- Trim branches that touch the roof above the garage, since climbing species use them as a route in
None of that replaces a door that seals. But a sealed door with a woodpile against the wall is still an invitation. If the door rubs, gaps or leaves daylight after new seals go on, the door itself needs adjusting, and that is part of our garage door repair service across Round Rock.
Making New Seals Last
Vinyl and rubber seals harden in the sun, and a west-facing door in Round Rock gets plenty of it. A few minutes twice a year stretches their life noticeably.
- Wipe the bottom seal and the side stop flaps with a damp cloth to clear grit, which abrades the rubber every time the door closes
- A light wipe of silicone spray on the flexible flaps keeps them supple through the summer; avoid petroleum products, which swell and soften rubber
- Check the top of the opening each spring, since wasps like to build in the gap above the door and a top seal gives them nowhere to start
- Look for chewed corners on the bottom seal, a sign that rodents are working at the gap
Seals are also checked as part of a tune-up, alongside the springs, rollers and opener. If the door needs other work, fitting new seals on the same visit costs far less than a separate call.
More From Our Advice Pages
- East or West of I-35: How Round Rock's Ground Moves Garage DoorsWhy doors east of the interstate gap and rub while west-side doors hold square, and what can be adjusted.
- What a Hard Freeze Does to a Garage Door in Round RockFrozen seals, cold-morning spring breaks and openers that quit, in the order a freeze tends to cause them.
Seal and Gap Questions
Can scorpions really get under a closed garage door?
Yes. A striped bark scorpion needs only a gap about the thickness of a credit card, and a worn bottom seal or a hardened side stop leaves far more than that. The daylight test finds the gaps they would use.
How often should a garage door bottom seal be replaced?
Every five to eight years in most Round Rock garages, sooner on west-facing doors that bake in the afternoon sun. When the rubber is hard, cracked or no longer touches the floor along its whole length, it is done.
Will a new bottom seal help with cedar allergies?
It helps, along with the side and top seals, because the garage is often where cedar pollen gets into the house on a windy January day. It will not fix a house that leaks pollen elsewhere, but it closes the biggest opening.
Can I replace the garage door bottom seal myself?
Usually, if the retainer is in good shape and you can get the right profile. The door has to be raised a few feet and secured, and the old seal slides out of the channel. Leave the bottom brackets and cables completely alone.
Why is there a gap under only one side of my garage door?
Either the door is out of level on its cables, or the slab has moved. A technician levels the door first. If the gap returns in a season, the slab is moving, which is common on clay soil east of I-35.
Light under the door? We can seal it on the same visit.
Open 24 hours. Bottom seals, perimeter stops and thresholds, priced before we start.