In this video, This Old House general contractor Tom Silva explains how to replace a threshold.
Steps for installing a new threshold
- Remove old threshold from doorway using hammer and reciprocating saw.
- Use reciprocating saw to cut the nails securing toekick; remove toekick.
- Test-fit new threshold in doorway.
- Build up toekick and subfloor with pressure-treated lumber; re-install toekick.
- Apply bead of tri-polymer caulk to joint between finished floor and new threshold.
- Install new threshold, then tap shims underneath.
- Close door and check for even gap along threshold.
- Open door, and apply expanding polyurethane sealant under the threshold.
- Close the door, then tap shims between door bottom and top of threshold; leave shims in place until the sealant cures.
- Sand threshold, then finish with an exterior paint or stain and topcoat that contains a ultra-violet protector.
Shopping list:
- New oak threshold
- Wood shims
- Tri-polymer caulk, for sealing joint between floor and threshold
- Expanding polyurethane sealant, used to adhere threshold
- Pressure-treated lumber, used to fill in subfloor and bolster toekick
- 100-grit sandpaper
- Exterior paint or stain and topcoat varnish
- 2-inch decking screws, used to fasten subfloor