How to Seal Your Garage Door Against Rodents

Gaps under your garage door are the primary highway for mice and rats looking to nest in your home. Even a tiny opening is an open invitation; if a rodent can fit its skull through a gap, the rest of its body will follow. A properly sealed garage door should leave no light visible between the rubber gasket and the concrete floor. Completing this project keeps your garage dry, energy-efficient, and, most importantly, critter-free. The goal is to create a physical barrier that is too tough to gnaw through and too tight to squeeze under. By replacing old, brittle seals with high-quality materials, you secure the perimeter and prevent common structural pests from finding a foothold.

Clear the Path First. Clear all debris, dirt, and dried oil from the concrete floor beneath the garage door. Use a stiff wire brush to ensure the area is perfectly flat and clean so the new seal adheres properly.
Strip the Old Guard. Open the garage door halfway and lock it in place. Slide the old rubber gasket out of the track at the bottom of the door; if it is stapled or nailed, pry the fasteners out with a flat-head screwdriver.
Size It Right. Measure the total width of the garage door opening. Cut your new EPDM rubber seal to length, adding an extra two inches to each side to ensure total coverage against the side door jams.
Slide Home the Seal. Feed the T-shaped ends of the new rubber seal into the door's track. Work slowly from one side to the other, ensuring the rubber slides evenly without bunching up inside the channel.
Lock Down the Sides. Install stainless steel rodent-proof side seals or weatherstripping along the vertical metal tracks. These should sit tight against the door when it is closed to prevent mice from scaling the sides.
Hunt Down the Light. Close the garage door fully and walk outside with the lights off inside the garage. If you see daylight streaming through anywhere, adjust the door limit settings or add extra-thick rubber backing to those specific spots.