Cracked Garage Door Weather Seal at the Bottom
A cracked weather seal — the rubber strip along the very bottom of your garage door — is a normal wear item you can usually replace yourself in about an hour for $15 to $40. On most modern steel and aluminum doors, the seal slides into a metal or vinyl track (the "retainer"), so the fix is mostly pulling the old gasket out and feeding a new one in. It's worth doing soon: a split seal lets in rain, drafts, dust, bugs, and the occasional mouse, and it makes your garage harder to heat and cool.
Step by step
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1
Confirm it's the seal and identify your retainer type
Run the door all the way down and look at the bottom edge. A bad seal shows as cracks, splits, flattened (mushroomed) rubber, daylight, or gaps where it no longer touches the floor. Now check how it's held on: most steel/aluminum doors have an aluminum or vinyl track (retainer) with one or two channels that the seal's T-shaped or beaded edges slide into. Wood doors usually have the seal nailed or stapled directly to the bottom board. Knowing which you have decides which replacement to buy.
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2
Measure and buy the right replacement
Measure the door's full width and add a few inches of slack. Then match the seal profile: T-style (one center T), bead/bulb style (two rounded edges), or a U-shaped 'astragal' for some doors. The fastest way to get an exact match is to pull a few inches of the old seal out and take it (or a clear photo with a ruler next to it) to the store. Note the retainer's groove width too — a 1/4-inch T won't seat in a 3/16-inch channel. Generic universal seals exist, but a profile match seals far better.
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3
Open the door and remove the old seal
Raise the door to a comfortable working height — chest level is ideal — so you can reach the bottom edge without crouching. For track-style retainers, slide the old seal out from one end; if it's brittle and tearing, cut it into sections and pull each piece. For nailed/stapled wood doors, pry the old gasket and fasteners off and scrape the wood clean. Wipe the empty track with a rag so grit doesn't fight you on the way back in.
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4
Feed the new seal in (the slippery-water trick)
Spray a little soapy water or silicone lubricant inside both retainer channels — this is the single biggest time-saver and keeps the rubber from binding. Start one edge of the new seal's T or beads into the channel at one end and work it across, feeding both sides into both grooves at the same time. A helper pulling from the far end as you push makes a wide door go much faster. Leave an inch or so of overhang on each end.
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5
Trim, seat, and test the seal
Once it's all the way through, trim the overhang flush (or leave it about 1/4-inch long so the ends stay sealed). For wood doors, position the new seal so it just touches the floor with the door closed, then staple or nail it every few inches. Lower the door and check from inside with the lights off: you shouldn't see a daylight gap. The seal should compress slightly against the floor without holding the door up off the ground.
When to call a pro
Call a pro if the gap is uneven side-to-side even with a fresh seal (that points to a bent bottom section, worn rollers, or a door that's off its tracks), if the retainer itself is bent or rusted through and needs replacing, or if your floor is so out of level that no standard seal closes the gap — those need a threshold seal or door adjustment rather than just a new gasket.
Call (888) 290-7421Frequently asked
How much does it cost to replace a garage door bottom seal?
If you DIY it, expect about $15 to $40 for the seal itself — a standard 16-foot rubber bottom seal runs roughly $20 to $35, plus a couple dollars for lubricant. If you hire a garage door company, the whole visit typically lands around $75 to $150 including the part and labor, depending on door width and seal type.
How long does a garage door weather seal last?
Most bottom seals last about 5 to 10 years, but it varies a lot with climate. Intense sun (UV), road salt, extreme heat-and-freeze cycles, and a rough or uneven concrete floor all wear rubber out faster. If yours is cracked, flattened, or letting in light, it's done — age aside, those are the signs to replace it.
Can I drive without — er, can I leave the door without a bottom seal for a while?
You can operate the door fine without a seal, but you don't want to leave it that way. The seal is your main defense against rain, snowmelt, drafts, dust, leaves, insects, and small animals getting under the door, and it cushions the door's contact with the floor. A missing or split seal also makes a heated or cooled garage much less efficient. It's a cheap, quick fix — worth doing within a week or two.
What's the difference between the bottom seal and the threshold seal?
The bottom seal (the part this article covers) attaches to the door and moves with it. A threshold seal is a separate rubber strip you glue to the garage floor where the door lands. They solve different problems: replace the bottom seal for normal wear, and add a threshold seal when your floor is uneven or slopes, when water keeps creeping in, or when you want extra sealing on top of a good bottom gasket. Many homeowners use both together.
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