Installing a Garage Door Bottom Weather Seal

Weatherproofing serves as the primary line of defense for your garage. Over time, the bottom seal—often called a threshold seal—cracks, dry rots, or loses its shape, leaving a direct invitation for mice, spiders, and wind-driven rain to infiltrate your space. A well-installed seal should sit perfectly flush against the floor without being crushed, creating a consistent barrier across the entire width of the door. Completing this project correctly requires more than just sliding a piece of rubber into a track. It involves thorough cleaning of the tracks and ensuring the door travel is adjusted so the seal touches the ground evenly. When done right, you will notice an immediate difference in garage temperature and a total cessation of unwanted visitors sneaking under the door.

Clear Access and Debris. Open the garage door fully to gain clear access to the bottom channel. Remove any lingering debris or old sealant residue from the track using a wire brush.
Extract the Old Gasket. Locate the ends of the door tracks. Use a screwdriver to pry back any crimps in the metal track that might be holding the seal in place, then pull the old gasket out through the side.
Scour Tracks Clean. Scrub the interior of the aluminum tracks with soapy water and a stiff brush. Ensure all grit and oxidation are removed so the new rubber can slide in without snagging.
Size the New Seal. Measure the width of your garage door and add two inches for trimming. Lay the new rubber seal on a flat surface and cut it to size using heavy-duty shears or a sharp utility knife.
Feed Seal Into Track. Have a helper hold one end of the seal while you feed it into the track. Move slowly along the length of the door, ensuring the T-ends of the rubber are seated correctly in the metal channels.
Crimp and Trim Ends. Once the seal is centered, use pliers to lightly crimp the ends of the metal track back into place to prevent the seal from shifting. Trim the excess rubber flush with the edge of the door.