Step 1: Mark and trim the door bottom
Photo 1: Trim the door
Scribe a line on the door 3/8 in. above the top of the threshold. Remove the door and carefully cut along the line with a circular saw.
Older wood doors usually rely on a non-adjustable threshold to keep the weather out. If your old door doesn’t seal tight against the threshold, you’re wasting energy. You could screw a surface-applied weather strip to the face of the door, but a door-bottom weather strip is a less obtrusive way to create a good seal.
The door bottom we’re using is available at most home centers and hardware stores. If you can’t find a door bottom that’s smooth on one side, you can slice off the barbed flanges from bottoms designed for steel or fiberglass doors.
Cut the bottom of the door to allow enough (but not too much) clearance to install the new door bottom. The goal is to create an even 3/8-in. space between the top of the existing threshold and the bottom of the door. Close the door and measure the largest gap between the door and the threshold. If the gap is less than 3/8 in., calculate how much you’ll have to cut off the bottom to equal 3/8 in. Mark this distance on the door at the point you measured. Then use a scribing tool to extend a mark across the bottom of the door (Photo 1).
Remove the hinge pins and move the door to a set of sawhorses. Mount a sharp blade in your circular saw and cut along the line. Protect the surface of the door with masking tape. If you have a veneered door, score along the line with a sharp utility knife before sawing it to avoid chipping the veneer.
Step 2: Install the new weather strip
Photo 2: Install the new weather strip
Cut the door bottom to length with a tin snips or utility knife. Apply two parallel beads of adhesive caulk the length of the door and nail the door bottom to the door.
Cut the door-bottom weather strip about 1/8 in. shorter than the width of the door and tack it to the bottom of the door with a staple gun. Rehang the door to test the fit. If it’s too snug, remove the weather strip and trim a bit more from the door. When the fit is perfect, remove the staples and mount the weather strip (Photo 2).
Video: Garage Door Weatherstripping
Required Tools for this Project
Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.
- 4-in-1 screwdriver
- Caulk gun
- Circular saw
- Scribing tool
- Staple gun
- Tape measure
- Tin snips
- Utility knife
Required Materials for this Project
Avoid last-minute shopping trips by having all your materials ready ahead of time. Here’s a list.
- 1-in. roofing nails
- Adhesive caulk
- Door bottom weather strip