Insulation · Buying guides · Updated November 2026
Weatherstripping vs. Caulk: Where Each Belongs
Weatherstripping and caulk both stop drafts, but they are not interchangeable. The rule of thumb: weatherstripping for things that open and close, caulk for gaps that stay put.
Where each belongs
| Spot | Use |
|---|---|
| Door edges and bottom | Weatherstripping and a door sweep |
| Window sashes that open | Weatherstripping |
| Attic hatch | Weatherstripping (foam tape or compression gasket) |
| Gaps between window or door trim and siding | Exterior caulk |
| Interior trim and baseboard gaps | Paintable acrylic latex caulk |
| Tubs, showers and sinks | Silicone or kitchen and bath caulk |
| Gaps larger than about a quarter inch | Backer rod plus caulk, or low-expansion foam |
Common weatherstripping types
- Adhesive foam tape: inexpensive; good for irregular gaps; wears out faster.
- V-strip (tension seal): for sides of double-hung and sliding windows.
- Compression bulb or kerf-in seals: for doors; durable.
- Door sweeps: close the gap under exterior doors.
Door sweeps and seals by door type
| Door | Good options | Notes |
|---|---|---|
| Standard exterior door | Kerf-in compression weatherstripping in the frame; screw-on sweep or replacement door bottom | Many newer frames have a slot (kerf) for push-in replacement seals |
| Door with a gap at an uneven threshold | Adjustable threshold or an automatic drop-down sweep | Make sure the door still closes and latches easily |
| Sliding patio door | Replacement pile weatherstripping and bottom seals made for that door | Use parts sized for your door model |
| Door from the house to the garage | Compression weatherstripping and a sweep | Helps keep fumes and drafts out; check any fire-rating requirements |
| Garage door | Bottom seal (often a replaceable retainer strip) and perimeter stop molding seals | See insulated vs. non-insulated garage doors |
| Storm door | Sweep and expander strip made for the storm door | Most come with a replaceable sweep |
Test after installing: close the door on a strip of paper. If it slides out easily, the seal is not making contact there.
Caulk types
- Acrylic latex: paintable, easy cleanup; best indoors.
- Silicone: flexible and waterproof; usually not paintable.
- Polyurethane or hybrid polymer: durable exterior sealants that adhere to many materials.
Do not seal these
- Weep holes at the bottom of window frames and brick walls.
- The bottom edge of lap siding, which needs to drain.
- Combustion air openings for furnaces and water heaters.
If drafts continue after sealing, see drafty windows and attic air sealing vs. insulation.
Cost figures are national ranges from the sources listed in our insulation cost guide, not a quote from FixFinch or any contractor.