Why small bathrooms cost more per square metre
Almost every bathroom contains the same fixed items regardless of size: a WC, a basin, a shower or bath, waste connections, an extractor, lighting, waterproofing and a strip-out. Those costs do not shrink when the room does.
A cloakroom still needs a plumber, an electrician and a tiler on site. Spreading three trades over 3 m2 rather than 9 m2 triples the apparent rate without anyone charging more.
Small rooms also cut more tiles. A high proportion of cut edges around a compact layout is slower work than laying full tiles across an open floor.
The practical takeaway: compare per-square-metre rates only against rooms of a similar size and specification. Comparing a cloakroom rate to a family bathroom rate tells you nothing.
Indicative rates by room size and spec
The figures below are planning ranges based on the sort of work we quote across Berkshire and north Hampshire. They include labour, materials, waste removal and VAT, and assume the layout stays broadly where it is.
| Room size | Standard spec | Mid-range spec | Premium spec | Typical rate per m2 |
|---|---|---|---|---|
| 2-3 m2 cloakroom | £1,800-£2,800 | £2,800-£4,000 | £4,000-£6,000 | £900-£2,000 |
| 4-5 m2 ensuite | £3,500-£5,000 | £5,000-£7,500 | £7,500-£11,000 | £875-£2,200 |
| 6-7 m2 family bathroom | £4,500-£6,500 | £6,500-£10,000 | £10,000-£15,000 | £750-£2,100 |
| 8-10 m2 large bathroom | £6,000-£8,500 | £8,500-£13,000 | £13,000-£20,000+ | £700-£2,000 |
What sits inside the rate
Strip-out and disposal, which is real labour plus real skip cost, not a rounding error.
First-fix plumbing and electrics, including any new circuits for lighting, shaver points and the extractor.
Waterproofing appropriate to the installation, from tile backer board behind a shower up to a fully tanked wet room floor.
Wall and floor tiling, adhesive, grout and trims, which is usually the single largest labour line.
Second fix, sanitaryware installation, sealing, testing and making good the surrounding decoration.
What sits outside the rate
Structural changes such as removing a stud wall, forming a new opening or dealing with a rotten floor.
Moving the soil stack or re-routing a main waste run, which is priced as its own item because the labour varies enormously.
Asbestos-containing artex or textured coatings, which need testing and licensed handling where relevant.
Whole-house issues that only surface once a floor comes up, such as failed pipework or inadequate joists under a heavy freestanding bath.
How to test a quote in five minutes
Measure the floor area, then divide the quoted total by that number. If the result sits far below the ranges above, something is missing rather than cheap.
Check the quote lists strip-out, waste removal, waterproofing, electrical certification and sealants as priced lines. Those four omissions account for most of the gap between a low quote and a final invoice.
Ask whether the figure includes VAT. Two quotes that look £1,400 apart are often the same price with different tax presentation.
Ask what happens if something is found behind the tiles. Our surveys look for it beforehand, and where a genuine unknown exists we say so before you commit rather than after.
Frequently asked questions
Is per square metre a reliable way to price a bathroom?
It is a good sanity check and a poor quoting method. Fixed items like the WC, extractor and waterproofing do not scale with floor area, so the rate only means something when you compare like-for-like room sizes.
Why is my ensuite quote nearly as much as the main bathroom?
Because it contains almost the same list of components and trades. The tiling area is smaller, but the plumbing, electrics, extraction and waterproofing are effectively the same job.
Do your quotes include VAT?
Yes. We give fixed written quotes including VAT, so the number you approve is the number you pay unless you change the specification.
Does a bigger bathroom get cheaper per square metre?
Generally yes, up to a point. Beyond around 8 m2 the extra area usually comes with extra specification such as a second basin or a freestanding bath, which pushes the rate back up.
How accurate can a price be before a survey?
We can give you a realistic band over the phone. The fixed price comes from a free no-obligation survey, because floor construction and drainage routes are what move the number.