A threshold, or door bar, is the strip that finishes the edge where one floor meets another, usually under a door. It protects the edge of each floor from wear, covers the expansion gap a floating floor needs, and smooths any difference in height so nobody trips. The right one depends on the two floors meeting and how much height there is between them. Getting it right also means checking the door will still open once the new floor, underlay or plywood overlay is down. Thresholds are part of every job we quote, and this guide explains how the choice is made.
Why thresholds are needed
Every floor edge left exposed at a doorway wears faster than the rest. Carpet frays, laminate and LVT edges chip, and vinyl can lift if it is scuffed repeatedly. A bar fixed over or against the edge takes that wear instead.
Floating floors, such as click laminate, must be able to move a little with the seasons. They need a gap at every doorway as well as at the walls, and the threshold hides it while leaving the floor free to move. Fixing a floating floor down at the doorway is a common cause of it lifting later.
Matching the bar to the floors
Carpet to carpet usually needs only a simple joining strip or a neat seam. Carpet to a hard floor needs a bar that grips the carpet edge on one side and sits over the hard floor on the other.
Hard floor to hard floor at the same height uses a flat bar. Where one floor is higher, a ramp profile takes up the difference. Where a hard floor stops at a step, patio door or tiled area, an end profile finishes the edge cleanly.
Finishes range from metal in silver, gold or bronze tones to wood effects and colours matched to the floor. The aim is for the bar to be noticed as little as possible.
- Carpet to carpet: joining strip or seam
- Carpet to hard floor: gripper-style bar
- Same-height hard floors: flat bar
- Different heights: ramp profile
- Floor ending at a step or door: end profile
Where height differences come from
A new floor rarely matches the old height exactly. Thicker laminate, a new underlay, a plywood overlay or a levelling screed can all raise the finished surface a few millimetres. 6mm ply, our standard overlay, is barely noticeable at the door, and transitions are finished with proper bars.
Mixing materials between rooms makes differences more likely: for example carpet on a thick underlay in the lounge beside LVT in the kitchen. Planning all the floors together means the heights can be matched rather than patched.
Doors that stop closing
Raise the floor and the door may catch. It is one of the most common surprises after new flooring, and it is avoidable. We check door clearances at the site visit and flag any door that may need trimming, so it is in the plan rather than discovered on the day.
Internal doors can usually be trimmed. Fire doors, external doors and some modern doors need more care, and in some cases a different floor build-up is the better answer.
Continuous floors without thresholds
Running the same floor through several rooms, such as LVT through a hall, kitchen and dining room, can remove the need for bars altogether and makes a small house feel larger.
Glue-down LVT copes with this well because it does not float. With click laminate, long unbroken runs need more thought about movement, and a threshold at some doorways may still be the right choice. We will say which is sensible for your layout at the site visit.
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Frequently asked questions
Are door bars included in a flooring quote?
They should be. Our quotes include thresholds, and a good quote lists them rather than leaving them out.
Why is my new floor higher than the next room?
A new underlay, thicker boards, a plywood overlay or screed can raise the floor. A ramp profile or careful planning of both floors handles it.
Will my door need trimming after new flooring?
Sometimes. We check door clearances at the site visit and flag any door that may need trimming.
Can I have one floor through several rooms with no bars?
Often, yes, especially with glue-down LVT. With click laminate, some doorways may still need a threshold for movement.
Why should laminate not be fixed at the doorway?
It is a floating floor and needs room to move. Pinning it at the doorway can make it lift into a ridge.