Understanding your result
The headline is the strips to buy, with the type, length and openings beneath it. The stats show how many doorways one strip covers and the cost; the table lists the doorways, any wide openings, the strip length, the strips, and the screws or track pieces.
Doorways per strip is the strip length divided by the doorway width plus an inch for the cut, rounded down. A 94 in strip covers two 36 in doors; a 72 in strip covers one. If the strip is shorter than one doorway, each door needs its own strip and possibly a joint. Wide openings, such as an arch between a living room and a dining room, take as many strips laid end to end as their width needs.
The type decides which strip to buy and is chosen from the floors on each side. The floor height calculator works out the difference and recommends the type; the expansion gap calculator says where a long floating floor needs a T-moulding; and for carpet edges the tack strip calculator lists them with the strip.
How we calculate this
The inch allowed per doorway covers the saw kerf and squaring the ends. The common strip lengths, 36, 72 and 94 inches, are the ones sold in US stores; metric strips are often 90 cm and 2.4 m. The expansion gaps guide explains why floating floors need a strip at long runs and doorways, the self-leveling guide covers raising a low floor, and the carpet roll guide covers carpet edges.
The assumptions behind the numbers
| Assumption | Default | Where it comes from |
|---|---|---|
| Strip length | 94 in (2.4 m metric) | Common transition strip length; 36 and 72 in are also sold |
| Door width | 3 ft (0.9 m) | A standard interior doorway |
| Cut allowance | 1 in per doorway | Saw kerf and squaring |
| Fixing | about 3 screws or track pieces per doorway | Typical track and screw spacing |
| Reducer limit | about 1/2 in | Typical reducer profiles; ADA 303 allows a 1:2 bevel up to 1/2 in |
Assumptions last reviewed October 8, 2026.
The calculator assumes all doorways are the same width. If they differ, run it for each width or enter the wide ones separately. It does not choose the type for you; the floor height calculator does that. And it does not count adhesive for glued strips or end caps at sliding doors, which are one per door.
Two worked examples
Four reducers where new laminate meets old vinyl
Four 36 in doorways, 94 in strips at $32.
- One strip covers floor(94 ÷ 37) = 2 doorways
- Strips: 4 ÷ 2 = 2 strips, $64
Two strips for four doors. A strip per door would have bought twice as many.
Carpet edges for two doors and an archway
Two 36 in doors and one 6 ft archway, 72 in strips.
- One 72 in strip covers floor(72 ÷ 37) = 1 doorway, so 2 strips for the doors
- Archway: ceil(72 ÷ 72) = 1 strip
- Strips: 3
The archway takes a full strip with nothing to spare; measure it carefully, because a 6 ft 1 in opening needs a second strip and a joint.
Where to find your inputs
Doorways. Count the openings where the new floor meets another floor.
Door width. Measure between the casings at floor level.
Wide openings. Measure each separately.
Strip length. From the store; matching strips in the flooring line often come in one length.
Common mistakes
- One strip per door. Long strips cover two doors.
- The wrong type. Choose it from the height difference.
- Screwing through the floating floor. Fix the track to the subfloor.
- No gap under the strip. Both floating floors need their gap.
- Generic strips with a premium floor. Matching strips cost more and look far better.
- Forgetting the sliding door. It needs an end cap.
Questions people ask
- How many transition strips do I need?
- One strip of 94 inches covers two standard 36 inch doorways with a little to spare, so three doorways need two strips. A 36 inch strip covers less than one 36 inch doorway once the cut is allowed for, so each door needs its own.
- What is a T-moulding for?
- Joining two floors at the same height, or breaking a long floating floor into sections. It sits over the gap between them and clips into a track fixed to the subfloor, so both floors can move under it.
- When do I need a reducer?
- When one floor is higher than the next by up to about 1/2 inch, such as laminate meeting vinyl. A reducer slopes down from the higher floor. For bigger differences, raise the lower floor first.
- What goes between carpet and a hard floor?
- A carpet edge, Z-bar or carpet-to-tile reducer that grips the carpet edge and steps down to the hard floor. The type depends on the hard floor's height; the floor height calculator compares them.
- Are transition strips sold to match the flooring?
- Many flooring lines include matching T-mouldings, reducers, end caps and stair noses in the same colour. They cost more than generic strips but match far better; order them with the floor.
- How are transition strips fixed?
- Most clip into a metal or plastic track screwed or glued to the subfloor, or are glued directly. They are never fixed through a floating floor.