Subfloor preparation on our site is priced from £12 per square metre. It covers the work that gives a new floor a flat, sound base: a 6mm or 9mm plywood overlay over uneven floorboards, a self-levelling latex screed over concrete, lifting and disposing of the old covering, and damp readings before anything goes down. Not every floor needs it. Good chipboard or a flat screed often goes straight to fitting. Old boards, tiles and uneven concrete almost always need something before LVT or vinyl. Below is what each option involves and what makes the figure rise.
Why preparation is priced separately
No two floors underneath are the same, even in houses on the same road. One room may have flat chipboard, the next patched Victorian boards, the kitchen old quarry tiles. A flat fee would either overcharge the easy floors or leave the hard ones unfunded, so preparation is assessed at the site visit and shown as its own line.
That also makes quotes comparable. If one quote includes preparation and another is silent on it, the cheaper one is not really cheaper; it has simply left out work that still has to be done.
Plywood overlays over floorboards
Floorboards move, cup and have gaps. Thin floors such as glue-down LVT and sheet vinyl show every edge through them within months. A plywood overlay fixed across the boards gives a single smooth surface instead.
We use 6mm ply as standard, which adds very little height at the door, and 9mm where boards are rougher. Transitions are finished with proper threshold bars. The cost depends on the area and how much fixing the boards need first, for example if loose boards have to be screwed down.
Self-levelling screed over concrete
Concrete floors are often out of level, patched, or scarred by old adhesive. A self-levelling latex compound is poured and spread to give a flat, smooth surface for the new floor to bond to.
Standard latex screed is walkable in two to four hours and ready for LVT the next day. Deeper fills take longer, and we advise on the day. The price rises with depth: a floor that needs a thin skim costs far less than one with a large dip to fill.
Uplift, disposal and damp checks
Lifting the old floor is part of preparation too. Carpet and underlay come up quickly. Glued vinyl, old tiles and bitumen adhesive take much longer and produce heavier waste, so they cost more to remove.
We take damp and moisture readings on solid floors. A floor that reads damp needs dealing with before any new covering, because moisture trapped under LVT, vinyl or laminate causes lifting and mould later.
- 6mm or 9mm plywood overlay
- Self-levelling latex screed
- Old floor uplift and disposal
- Damp and moisture readings taken
Does your floor need it? A quick self-check
Lay a long straight edge, such as a spirit level, across the floor in a few directions. Big gaps under it mean the floor is out of flat.
Walk the room in socks. Soft spots, creaks and boards that dip underfoot point to a subfloor that needs attention before hard flooring.
Look at what is there now. Tiles that sound hollow when tapped, old vinyl with ridges, and floorboards with visible gaps all usually mean preparation for LVT or vinyl. Laminate and carpet are more forgiving, and sometimes need little or none.
Our guide on whether you need a new subfloor covers the bigger problems, such as rot or a breaking slab, that go beyond routine preparation.
Want this priced for your own rooms?
We measure, check the subfloor and give you an itemised written quote - free, with no obligation, across South East London and Kent.
Frequently asked questions
How much does subfloor preparation cost?
Our subfloor preparation is priced from £12 per square metre. The type of work, the depth of any screed and what has to be lifted first set the final figure.
Do I always need subfloor preparation?
No. Good chipboard or a flat screed often needs none. Old floorboards, tiles or uneven concrete usually do before LVT or vinyl.
How long does levelling screed take to dry?
Standard latex screed is walkable in two to four hours and ready for LVT the next day. Deeper screeds need longer.
Will a plywood overlay raise my floor?
6mm ply is barely noticeable at thresholds, and transitions are finished with proper bars. 9mm is used where the boards are rougher.
Can I skip preparation to save money?
You can on a floor that is already flat and sound. On a poor floor, skipping it means the new floor shows every flaw and fails sooner.