The short answer
Choose the Right Weatherstrip
Start by measuring the gap between the door and the jamb when the door is closed. Use a tape measure at several points along the top and sides. A gap of 1/8 inch or less works well with adhesive foam tape. Wider gaps need a V-strip or a metal-backed sweep.
For the bottom of the door, a door sweep with a rubber fin is your main defense against rain. You attach it to the inside face of the door so it presses against the threshold. Pick a sweep that matches your door's width and the height of the gap. Most hardware stores sell these in standard lengths you can trim.
- Measure the gap at top, sides, and bottom.
- Foam tape works for gaps under 1/8 inch.
- V-strip suits gaps up to 1/4 inch.
- Door sweeps cover the bottom edge.
- Clean and dry all surfaces before applying.
Prep the Door and Jamb
Remove old weatherstrip and any adhesive residue with a putty knife or a mild solvent. Wipe the door stop and jamb with a damp cloth to remove dust and dirt. Let the surface dry completely. A clean, dry surface lets the adhesive bond properly.
Check the door for gaps where water might sneak through, like cracks in the frame or missing caulk. If you find rot or damage, you may need door frame repair before adding new weatherstrip. Water that gets behind the seal can lead to more serious issues.
Apply the Weatherstrip
Peel the backing off the foam tape or V-strip and press it into place along the door stop. Start at the top and work down the sides. Use firm, even pressure to make sure it sticks. For V-strip, position the V so it opens toward the outside of the door, which helps it flex and seal.
For the door sweep, hold it against the door bottom with the rubber fin touching the threshold. Mark the screw holes, then attach it with the included screws. Adjust the fin so it compresses slightly when the door closes. You want a snug fit without the door sticking.
Test and Adjust the Seal
Close the door and check for light coming through the gaps. That light shows where air and water can pass. Open and close the door a few times to see if the weatherstrip stays in place and the door moves smoothly. If the door drags, trim the weatherstrip or adjust the sweep.
A good seal keeps out rain, but it also keeps out drafts and insects. If you notice water pooling on the threshold after a storm, check the bottom sweep again. Sometimes the threshold is uneven, and you might need a thicker sweep or a new threshold.
Know When to Call a Pro
Weatherstripping is a doable weekend project for most doors. But if your door frame is warped, rotted, or misaligned, new weatherstrip alone won't stop the rain. In that case, local water damage pros can inspect the frame and surrounding wall for hidden damage.
Water that gets past the door can soak into drywall, flooring, and framing. If you see stains, soft spots, or a musty smell, that's a sign of deeper water damage. A water damage inspection can find the source and help you decide on repairs. Acting quickly reduces the risk of mold.
- Check for rot in the door frame.
- Look for water stains on nearby walls.
- Feel for soft spots in the flooring.
- Notice any musty odors after rain.
- If damage exists, get a professional inspection.
Water damage does not wait
Call (801) 383-0232 any time, day or night, and describe what happened.
Call Now (801) 383-0232Frequently asked questions
What type of weatherstrip is right for a door that gets heavy rain?
For heavy rain, a door sweep at the bottom and V-strip on the sides offer the most durable seal. Foam tape is fine for moderate weather but can compress over time. Choose a sweep with a thick rubber fin that presses firmly against the threshold.
How often should I replace door weatherstripping?
Check your weatherstrip at least once a year, especially before rainy season. If it feels hard, cracked, or no longer springs back, replace it. A simple test is to close the door on a piece of paper; if you can pull it out easily, the seal is weak.
Can I weatherstrip a door that already has water damage?
It's not a good idea to seal over rot or mold. Water trapped behind new weatherstrip can worsen the damage. First, dry the area and address any rot or mold. If the door frame is compromised, have a professional inspect it before you install new weatherstrip.