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Garage door weather stripping is the set of rubber and vinyl seals around the door. There's a bottom seal along the base of the door, a threshold seal on the floor (optional), and stop molding along the sides and top of the frame. In South Florida, these seals keep out wind-driven rain, sand, leaves, lizards, roaches, and hot, humid air. Most seals need replacing every few years here, because our sun, heat, and humidity break rubber and vinyl down faster than in milder climates. You can see daylight under or around a door with worn seals, and you'll often find water or debris inside after a storm.
Here's how each seal works, how to tell when yours are worn out, which type fits your door, and when to have them replaced professionally.
The four seals on a garage door
1. Bottom seal (the "astragal")
This is the flexible strip along the bottom edge of the door, and it does most of the work. It closes the gap between the door and the floor, which is rarely perfectly level. Bottom seals come in several shapes:
- T-style and beaded seals slide into a channel, called a retainer, on the bottom of steel doors. These are the most common on modern sectional doors.
- Bulb seals have a round, hollow profile that compresses to fill uneven floors.
- J-style seals hook into certain retainer designs.
- Nail-on or screw-on seals attach directly to the bottom of older wood doors.
The right replacement depends on your retainer's shape and width, so it's worth measuring or bringing a piece of the old seal when you shop.
2. Bottom retainer
The aluminum or vinyl channel that holds the bottom seal. In coastal and humid garages, aluminum retainers can corrode and vinyl ones can crack. A damaged retainer won't hold a new seal properly, so it sometimes needs replacing along with the seal.
3. Side and top stop molding
These are the strips nailed or screwed to the door frame (the jambs and header) with a soft flap that presses against the face of the closed door. They block light, rain, and pests from getting in around the sides and top. Vinyl stop molding is common. In salt air, look for versions with corrosion-resistant fasteners.
4. Threshold seal (optional)
A rubber hump glued to the garage floor under the door. It's useful when the slab slopes toward the garage, has low spots, or lets rain run inside. It works together with the bottom seal to form a tighter barrier. A threshold seal does change how the door meets the floor, so the opener's close limit may need adjusting afterward.
Why seals wear out faster in South Florida
- UV and heat. Direct sun bakes the bottom seal and stop molding, making them hard, brittle, and cracked. West-facing garages get it the worst.
- Humidity and salt air. Moisture and salt corrode retainers and fasteners, especially near the Intracoastal and the beach.
- Wind-driven rain. Summer storms and tropical systems push water sideways under and around the door. A tired seal lets it in.
- Pests. Lizards, palmetto bugs, ants, and rodents use any gap as a doorway. Some will chew soft seals.
- Daily use. A door that opens and closes several times a day compresses and scuffs the bottom seal every time.
Signs it's time to replace your weather stripping
Check your seals at least twice a year, at the start of hurricane season and again in the fall. Replace them if you see:
- Daylight under the door or along the sides when it's closed
- Water on the garage floor after rain, or a water line along the door
- Sand, leaves, or debris blowing in under the door
- More bugs or lizards in the garage
- A cracked, flattened, torn, or hardened bottom seal
- A seal that's pulled out of the retainer or hangs in loops
- Stop molding that's warped, split, or no longer touches the door
- A hotter garage than usual, or AC working harder in rooms next to the garage
A quick test: close the door at midday, turn off the garage lights, and look for light around the edges. Any light coming in means air, water, and insects can get in too.
Can you replace a garage door bottom seal yourself?
Many homeowners can replace a slide-in bottom seal themselves. The basic process:
- Open the door to a comfortable working height, then unplug the opener and lock the door in place with clamps or locking pliers on the track, just above a roller. That keeps it from moving while you work.
- Slide the old seal out of the retainer. If it's stuck, a little dish soap and water helps.
- Clean the retainer channels and check for corrosion or cracks.
- Feed the new seal into the channels from one end. Soapy water makes this much easier. Two people help on a double door.
- Trim the seal to length, leaving a little extra so it can compress at the ends.
- Remove the clamps, plug the opener back in, and close the door to check the fit.
- Test the auto-reverse. Lay a 2x4 flat under the door and close it. The door should reverse when it touches the board. A thicker seal can change how the door meets the floor, so the opener's close limit may need adjusting.
What not to touch: The bottom brackets at each lower corner of the door hold the lift cables and are under high spring tension. Never loosen those brackets to replace a seal. If your retainer is attached in a way that requires removing them, call a professional.
When to call a professional
Get help with your weather stripping when:
- The retainer is corroded, bent, or cracked and needs replacing
- Your door is wind-rated or impact-rated and you want parts that match its design. Learn more in Does My Garage Door Have to Be Hurricane-Rated?
- Water comes in even with a new seal. That points to a sloped slab, an uneven floor, a door that sits crooked, or springs that are out of balance.
- The door doesn't sit evenly on the floor, or one side touches before the other
- You'd rather have the bottom seal, stop molding, and threshold done at once and the opener re-tested
An uneven gap under the door often means the door is out of balance or a cable or spring is wearing out. That's worth a look before it becomes a bigger repair. See Broken Garage Door Spring? What South Florida Homeowners Need to Know.
Weather stripping and hurricane season
Weather stripping doesn't make a door hurricane-rated. Wind resistance comes from the door's construction, struts, and hardware. But fresh seals keep out the wind-driven rain and debris that come with storms. Pair a seal check with the rest of your storm prep using The South Florida Hurricane Playbook for Your Garage Door.
Tips to make your seals last longer
- Rinse the bottom seal and stop molding with fresh water a few times a year, especially near the coast, to remove salt and grit.
- Keep the track area and floor clean so the seal isn't pressing down on sand or gravel.
- Avoid harsh cleaners and petroleum-based products on rubber and vinyl. They can make seals swell or crack.
- Lubricate the door's moving parts (not the seals) with a garage-door-rated lubricant so the door closes smoothly instead of slamming into the floor. See How to Lubricate Your Garage Door.
- Watch for rust on the retainer and fasteners. Our garage door rust prevention guide explains how to stay ahead of corrosion.
Frequently asked questions
How often should garage door weather stripping be replaced in Florida? There's no fixed schedule. In South Florida's sun and humidity, seals often need replacing every few years. Inspect them twice a year and replace them when you see cracks, gaps, or daylight.
What type of bottom seal do I need for my garage door? It depends on your door's retainer. Most modern steel doors use a T-style or beaded seal that slides into an aluminum or vinyl channel. Measure the channel or bring a piece of the old seal to match it.
Why is water getting under my garage door? Common causes are a worn bottom seal, a sloped or uneven slab, a door that sits unevenly, or wind-driven rain during storms. A new bottom seal, a threshold seal, or both usually fixes it.
Will new weather stripping keep bugs and lizards out of my garage? It helps a lot. Most pests get in through gaps under and around the door, so a tight bottom seal and good stop molding cut down on them significantly.
Does a new bottom seal affect my garage door opener? It can. A thicker seal changes where the door meets the floor, so the opener's close limit may need a small adjustment. Always test the auto-reverse afterward.
Keep the rain, sand, and pests outside
Ultra Garage Doors replaces bottom seals, retainers, stop molding, and threshold seals across Broward and Palm Beach County. Every visit includes a balance and safety check, so you know the door is closing evenly and safely. Seal replacement is part of our residential garage door services, and repairs start at $70.
Call 561-494-4070 or request service online.