How to Weatherstrip a Garage Door: Step-by-Step

Weatherstripping your garage door seals the gaps around it, keeping out rain, drafts, dust, and pests. It also improves energy efficiency by reducing heat loss in winter and keeping cool air inside during summer. This guide covers the entire process—from choosing the right material to installing it correctly—so you can do the job in an afternoon.

What You’ll Need

• Weatherstrip material (vinyl, rubber, or foam—choose based on your door type and gap size)
• Measuring tape
• Utility knife or scissors
• Pry bar or flathead screwdriver (for removing old weatherstrip)
• Cleaning supplies (rag, mild detergent, water)
• Adhesive (if using adhesive-backed weatherstrip) or fasteners (nails or screws) if not pre-slotted
• Caulk or sealant (optional, for extra sealing)
• Safety glasses and work gloves

Step-by-Step

1. Measure the door. Measure the width and height of your garage door. You’ll need enough weatherstrip to cover the top and both sides (the bottom usually uses a different type called a bottom seal). Add a few inches for cutting errors.
2. Choose the right weatherstrip. For the sides and top, use a rigid vinyl or rubber strip with a flexible lip that presses against the door. For the bottom, use a rubber or vinyl bulb seal that attaches to the door’s bottom edge. Check the gap size—if it’s larger than a quarter inch, you may need a thicker or double-seal type.
3. Remove old weatherstrip. Use a pry bar or flathead screwdriver to gently pry off the old strip. Be careful not to damage the door frame. If the old strip is nailed, pull out the nails. If it’s glued, scrape it off with a putty knife.
4. Clean the surface. Wipe down the door frame where the new weatherstrip will go. Use a rag with mild detergent and water to remove dirt, grease, and old adhesive residue. Let it dry completely.
5. Install the top weatherstrip. Start at the top of the door. Cut the strip to the door’s width. If it has a pre-slotted channel, slide it onto the frame. If not, use adhesive or small nails. Press the flexible lip so it bends slightly toward the door—this ensures a tight seal when the door is closed.
6. Install the side weatherstrips. Measure each side from the top corner to the bottom. Cut the strip to length. Attach it the same way as the top, making sure the lip faces inward toward the door. The strip should touch the door lightly but not be compressed so much that it prevents the door from closing.
7. Install the bottom seal. The bottom seal typically slides into a channel on the door’s bottom edge. Remove the old one by sliding it out. Slide the new one in, starting from one end. If it’s too long, trim it with scissors. Make sure the seal touches the floor evenly.
8. Test the door. Close the garage door and check for gaps. You should see the weatherstrip compress slightly but not be fully flattened. Open and close the door a few times to ensure it moves smoothly without dragging.
9. Make adjustments. If you notice gaps, adjust the strip’s position. For side strips, you can loosen the fasteners and move them slightly. For the bottom seal, you may need to adjust the door’s travel limit or the seal’s thickness.
10. Seal any remaining gaps. If there are small gaps at the corners or where the strips meet, apply a bead of caulk or sealant to fill them. Smooth it with your finger or a tool.

Common Mistakes

• Buying the wrong type. Not all weatherstrip is the same. Using a bottom seal on the sides won’t work, and vice versa. Check the product label for its intended use.
• Measuring incorrectly. Measuring only one side and assuming the other is the same can lead to shortages. Always measure each side separately.
• Overlapping the strips. At corners, strips should butt together neatly, not overlap. Overlapping creates a bump that can prevent the door from closing flush.
• Compressing the weatherstrip too much. If the strip is too thick or installed too tightly, the door may not close fully, or the opener may struggle. Aim for a gentle contact.
• Skipping the cleaning step. Adhesive won’t stick well to a dirty surface, and nails may not hold. Always clean and dry the area first.

Tips

• Do this on a mild day. Weatherstrip is easier to work with when it’s not too hot or cold. Extreme temperatures can make it brittle or too soft.
• Use a helper. For long strips, having someone hold one end while you attach the other makes the job easier and more accurate.
• Check the door’s alignment. If your door is crooked or has gaps that weatherstrip can’t fix, you may need to adjust the track or hinges. Weatherstrip is not a substitute for proper door maintenance.
• Consider a threshold seal. If your garage floor is uneven, a rubber threshold seal that sits on the floor can complement the bottom seal.
• Keep spare material. Buy a little extra so you can replace a damaged section later without a full redo.

Troubleshooting

• The door won’t close all the way. The weatherstrip is too thick or installed too tightly. Remove it and trim the lip or use a thinner type. Also check that the door’s limit switch isn’t set too low.
• Water still gets in. Check the bottom seal—it may not be touching the floor evenly. Adjust the door’s travel or add a threshold seal. Also inspect the corners where side and top strips meet; seal any gaps with caulk.
• The weatherstrip keeps coming off. If using adhesive, the surface wasn’t clean or dry. Remove the strip, clean again, and reapply with a stronger adhesive. If using nails, they may be too short—use longer ones.
• The door is noisy. The weatherstrip may be rubbing too hard. Loosen the fasteners and reposition the strip so it barely touches the door. Lubricate the rollers and hinges as well.
• The strip is too long or short. Measure twice, cut once. If it’s too long, trim it with scissors or a utility knife. If it’s too short, you can piece it together, but it’s better to replace with a proper length.

Frequently Asked Questions

• How often should I replace garage door weatherstripping? It depends on the material and climate, but generally every few years. If you see cracks, gaps, or it’s no longer flexible, it’s time to replace it.
• Can I use adhesive-backed foam tape instead? Yes, for small gaps, but it’s less durable and may not provide a good seal for larger gaps. For best results, use a rigid strip with a flexible lip.
• Do I need to weatherstrip the bottom of the garage door? Yes, the bottom seal is crucial for keeping out water, leaves, and pests. It also helps with insulation.
• How do I know what size weatherstrip to buy? Measure the gap between the door and the frame. Most weatherstrip is designed for gaps up to a certain width. If in doubt, choose a size that’s slightly thicker but still compressible.
• Can I install weatherstrip on a metal garage door? Yes, the process is the same. Just make sure the surface is clean and use fasteners that are appropriate for metal (like self-tapping screws).
• Will weatherstripping make my garage door harder to open? If installed correctly, it should not. The strip should compress slightly but not create significant drag. If the door is hard to open, the strip is too tight.