Garage Door Weatherstripping on the Sides and Top: Check, Fix, Replace

When people think about sealing a garage door, they usually think about the rubber strip along the bottom. But the sides and top of the door matter just as much. If you can see daylight around the edges of a closed door, air, water, dust and bugs can come in the same way.

What side and top weatherstripping is

On most homes, the door frame is lined with a strip often called stop molding or a perimeter seal. It has a rigid part that is nailed or screwed to the frame and a soft, flexible flap that faces the door. When the door closes, the flap rests against the face of the door and closes the gap.

Some doors also have a separate seal along the top of the frame. The bottom seal is a different part, attached to the door itself. We cover it in our guide to the garage door bottom seal.

Signs it is worn

• Daylight showing around the sides or top of a closed door
• Drafts, dust or leaves collecting along the inside edges
• Water stains or puddles near the side walls after rain
• A flap that has gone hard, cracked or flat
• A strip that is pulling away from the frame or has gaps between pieces
• Old paint caked on the flap, which keeps it from flexing

Sun and heat are hard on vinyl, so the side facing the afternoon sun often wears first. See garage door care in hot, sunny climates for more on that.

The lights off check

This is the easiest way to find gaps. Close the door, step inside the garage and turn off the lights during the day. Look along both sides and the top. Any line of light is a gap. Note where it is.

You can also run your hand along the edges on a windy day to feel for drafts, or look for small piles of dust and leaves after a storm.

When the gap is not the weatherstripping

Sometimes the seal is fine and the door is the problem. If the gap is much wider at one spot, or wider on one side than the other, the door may be sitting crooked or the frame may have shifted. A door that hangs lower on one side can point to a cable or spring problem.

If you see that, don't try to close the gap with a thicker seal. Have the door checked. Our posts on cable warning signs and a door that is off track explain what to look for.

Replacing side and top weatherstripping

This is a reasonable homeowner project for most doors. Take your time, and keep safety first.

• Close the door and unplug the opener. That way no one runs the door while you are working.
• Work from outside. The strip is on the outside of the frame. You don't need to be near the springs, which are inside above the door.
• Measure and match. Measure each side and the top, and take a photo of the old strip's profile so you can match it.
• Remove the old strip. Pull the nails or screws carefully so you don't split the frame. Check the wood underneath for rot or soft spots.
• Set the new strip lightly. Hold it so the flap just touches the face of the closed door. Then fasten it.
• Work in sections. Do one side, then the other, then the top, overlapping or butting the corners neatly.

Don't set it too tight

This is the most common mistake. If the flap presses hard against the door, the door has to drag past it every time it moves. That can make the door stick, wear the finish and make the opener work harder than it should. A light touch is all it takes to seal.

Test the door when you are done

Plug the opener back in and run the door a few full cycles. Watch for any dragging, scraping or hesitation where the new strip meets the door. Then test the safety reverse following your opener manual. Our guide on how to test your safety sensors and auto-reverse walks through it.

If the door hesitates or reverses after the new seal goes on, loosen and reset the strip so it touches more lightly. Don't adjust the opener to push through it.

Keep it in good shape

• Look at the seals at each change of season
• Wipe them clean with mild soap and water
• Don't paint the flexible flap
• Keep stored items from leaning against the edges of the door

A good seal on all four sides helps keep the garage cleaner and drier. Our garage door maintenance checklist puts seal checks on the seasonal list alongside the other quick jobs.