How to Install a Transition Strip: T-Molding and Reducers
To install a transition strip between two floors, leave a gap between the floor edges as wide as the molding’s track or base requires, fasten the track or adhesive to the subfloor, and press or tap the strip into place. The strip must attach to the subfloor, never to a floating floor, so both floors can expand and contract. Choose the profile by the height difference: a T-molding for floors of equal height, a reducer when one is lower.
Tools and materials
- Transition molding and its metal or plastic track, if supplied
- Tape measure, pencil and speed square
- Miter saw or fine-tooth handsaw
- Drill with masonry bit and plugs for concrete, or wood screws for plywood
- Construction adhesive, if the molding is glued
- Rubber mallet and a scrap block
- Painter’s tape to hold the strip while adhesive sets
Choosing the right transition strip
| Profile | Use | Height difference |
|---|---|---|
| T-molding | Joining two hard floors of similar height | None or very small |
| Reducer | Hard floor stepping down to vinyl, tile or concrete | Moderate |
| Carpet transition | Hard floor meeting carpet | Varies |
| End cap or threshold | Edge at a sliding door, fireplace or step | Floor edge only |
| Stair nose | Top edge of a step or landing | Step edge |
Many manufacturers sell a multi-purpose molding that can be set up as a T-molding, reducer or end cap. Matching moldings for discontinued floors can be hard to find, so a neutral wood or metal strip is a common substitute.
Step 1: Measure the height of both floors
Measure each finished floor from the subfloor up, including underlayment. A difference of a few millimeters suits a T-molding; larger differences need a reducer. When joining a close match to an existing discontinued floor, choose products of the same thickness so a T-molding sits flat. The guide on telling laminate from vinyl plank helps confirm what the existing floor is.
Step 2: Set the gap between the floors
Check the instructions for the track width and the required expansion space on each side. A common arrangement leaves a gap of roughly 1/2 to 3/4 inch between the two floor edges for a T-molding. Place the joint under the center of a closed door so the strip is not visible from either room.
Step 3: Cut the molding to length
Measure the opening at the gap, from door jamb to door jamb. Cut the molding with a miter saw for a square, clean end. Cut the track about 1/4 inch shorter than the molding so it stays hidden.
Step 4: Fasten the track to the subfloor
On a wood subfloor
Center the track in the gap and screw it down through the predrilled holes, keeping screw heads flush so the strip seats fully.
On concrete
Drill holes for plastic plugs, insert them, then screw the track down. Some tracks can be glued with construction adhesive instead.
Step 5: Install the strip
Align the molding over the track and press it in by hand along its length. Tap it down with a rubber mallet over a scrap block to avoid denting the surface. For glued moldings without a track, apply adhesive to the subfloor only, set the strip and hold it with painter’s tape until cured.
Common mistakes
- Gluing or nailing the strip to a floating floor, which pins the floor and can cause gaps or buckling.
- Leaving too little gap for the molding’s base, so the strip rocks or lifts.
- Using a T-molding over a large height difference, creating a trip edge.
- Placing the joint in the open doorway instead of under the door.
Using transitions to blend a close match
A transition at a doorway lets a close substitute sit next to a discontinued original without the eye comparing them plank to plank. This approach is covered further in finding a replacement plank for discontinued laminate and how to reuse closet flooring planks.
Frequently asked questions
Do I need a transition strip between two rooms of laminate?
Most laminate makers require a break at doorways and in long runs, though limits differ by product. Check the installation guide for maximum room dimensions.
Can a transition strip be installed after the floor is down?
Yes, if a gap was left between the floors. If the floors were butted together, trim one edge with an oscillating tool to make room for the track.
How do I remove an old transition strip?
Pry up gently at one end with a flat bar over a scrap of wood. Most strips lift out of their track; glued strips may need the adhesive cut with a putty knife.
Photo: Tomwsulcer, CC0, via Wikimedia Commons.
More how-to guides: See all of our discontinued flooring how-to guides.
