Floor Levelling near you

Most floor levelling in an existing home is not controlled work, but the moment the project is about accessibility the regulations become specific. Approved Document M volume 1, the 2015 edition with 2016 amendments, defines an accessible threshold as a threshold that is level or, if raised, has a total height of not more than 15mm, a minimum number of upstands and slopes, and any upstands higher than 5mm chamfered. That is the figure that ends arguments about a doorbar between two rooms of different build-up, and it is a useful target even where the regulations do not bite.

The approved document also flags the tension that levelling work creates. It notes that in meeting Part M by providing a level or ramped approach and level threshold, care must be taken to ensure the moisture resistance and design of the dwelling as a whole also complies with requirements C2 and C4 — in other words, taking a floor up to meet an external door without thinking about damp simply moves the problem. It adds that where both Part M and Part K apply to a stepped or ramped approach, the Part M requirement takes precedence.

Approved Document M applies in England, with Wales publishing its own version. Scotland works to the building standards technical handbook and Northern Ireland to Technical Booklet R, Access to and use of buildings, under the Building Regulations (Northern Ireland) 2012. If the levelling work is part of an adaptation for someone with limited mobility, ask the contractor to state the finished threshold height at every doorway as a number in the quotation.

Almost every failed pour traces back to the surface it was poured onto. Levelling compound is a bonded layer, so it can only be as good as its grip on the base, and the base is usually the part that was rushed. Dust left after grinding, a curing compound on a newer slab, the weak laitance on top of a gypsum screed, old flexible adhesive residue, or simply a primer applied too thinly or at the wrong dilution will all produce the same symptom: a hard, apparently perfect surface that later sounds hollow underfoot and eventually breaks up in plates. None of that is visible on the day the compound goes off.

The second family of failures is about water, and it runs both ways. A compound poured too wet loses strength and can crack or shrink as it dries; a compound dried too fast with a fan heater does the same. In the other direction, a solid ground floor that is still giving off moisture will keep doing so under whatever is laid on it, which is why the moisture reading belongs in the paperwork before a membrane is chosen. Gypsum-based products deserve their own warning here, since they are not intended to stay wet, and a gypsum screed in a room that floods is a repair rather than a dry-out.

The third is movement. A timber floor deflects, and a rigid cementitious compound poured directly onto springy boards will crack along the lines of the joists as soon as someone walks on it. The answer is either a flexible, fibre-reinforced product made for timber, or a plywood overlay screwed down at close centres to stop the movement first. A contractor who asks what the subfloor is before quoting a price per square metre is asking the right question.

Thickness is the hidden constraint in every levelling job, and it is easier to solve on paper than on site. Adding build-up changes the gap under every internal door, the clearance at the front door, the height of the bottom step of the stairs — which becomes a trip hazard if it ends up different from the others — the fit of a fitted kitchen's plinths, and the position of a radiator's pipework where it comes through the floor. Work the finished floor level out first, then choose the levelling method, rather than the other way round.

Where the floor is being rebuilt rather than merely levelled, the approved documents recognise this problem directly. Approved Document L volume 1's guidance on renovating a floor gives, as a typical construction, replacing a screed with an insulated floor deck to maintain the existing floor level, and the notes to its table of limiting U-values accept that a lesser standard may be appropriate where meeting the target would create significant problems in relation to adjoining floor levels. That is an acknowledgement that in an existing British house you sometimes cannot have both the insulation thickness and the original doorway heights, and that the trade-off should be made deliberately.

Levelling is priced on depth and on preparation more than on floor area. What moves the number is how far out of flat the floor is and therefore the average thickness required, whether the base is concrete, screed or timber, how much mechanical preparation is needed to get back to a sound surface, whether a damp-proof membrane or a moisture suppressant system is required, how many rooms and doorways are involved, whether a ply overlay is needed as well as or instead of a compound, and how the material gets into the room — a pumped pour and a hand-mixed one are very different operations. Drying time also costs, because the finished floor cannot be laid until the compound is ready.

This is the sort of job LokalMatch is useful for precisely because it is hard to describe twice. Set it out once with your postcode — the rooms, what the floor is made of, roughly how far out it is and what is going on top — and pros covering your area contact you about it. Homeowners pay nothing to post a job, and the professionals pay for the requests they receive. LokalMatch does not level floors, does not set prices and does not vet, rank or recommend anyone who replies, so checking the primer, the membrane and the finished threshold heights is your part of the work.