The materials cost is rarely the problem. The problem is what happens underneath the tile, before a single one goes on the wall, and that part is almost invisible until the grout starts cracking eighteen months later. In a Central London flat, where floors move slightly, walls are rarely square, and a wet room sits directly above a neighbour's ceiling, the margin for a rushed job is smaller than it looks.
This is a short guide to the questions that actually separate a tiler who will still be answering your calls in two years from one who has already moved on to the next postcode.
Start with what's under the tile, not on it
Anyone can lay a straight tile on a flat, dry surface. The job that matters is the preparation underneath, and in a bathroom or wet room that means proper waterproofing before tiling begins — not a coat of sealant applied as an afterthought once the grout is in. Ask specifically how the shower area and floor will be tanked, and what happens at the junctions where floor meets wall and where a shower tray meets the upstand. If the answer is vague, that's the answer. Our guide to wet room waterproofing and tanking sets out what a proper build-up actually looks like, and it's worth reading before you get quotes so you know what to ask for.
Outside bathrooms, the equivalent question is substrate flatness. Older Central London buildings rarely have a floor or wall that's perfectly true, and a tiler who skips levelling compound to save a day will leave you with lippage — tile edges sitting slightly proud of each other — that's obvious the moment light crosses the room at an angle.
Ask about the tile size before you ask about the price
Large format tiles have become the default look in London flats and bathrooms, and they're less forgiving than smaller formats: they need a flatter substrate, back-buttering, and a levelling system to stop edges sitting proud once the adhesive cures. A tiler who's confident with 200mm mosaics isn't automatically confident with a 1200mm porcelain slab. Our piece on large format tiles in a London flat covers what changes with bigger formats and why it affects both the quote and the timeline. If you've chosen a large tile, ask to see recent examples of that size specifically, not just tiling in general.
Understand what the price per square metre actually includes
Tiling is normally quoted as a labour rate per square metre, with materials — tiles, adhesive, grout, trims — priced separately or supplied by you. Our own tiling labour starts from £55/m², and what varies that figure is tile size, layout complexity (herringbone or diagonal patterns take longer than a straight lay), and how much substrate preparation is needed before a tile can go down at all. A fixed, itemised quote should say clearly what's labour-only and what, if anything, is included for prep work, waste removal, and edge trims. Our guide to tiling cost per m² in London breaks down what drives the number up or down so you can sense-check a quote before you sign it.
Ask what happens if the existing tiles are staying
Not every job is a full retile. Sometimes a bathroom just needs the grout replaced, or a handful of cracked tiles swapped out, and a tiler worth hiring will tell you honestly when that's all you need rather than pitching a full strip-out. The decision between a full retile and a targeted regrout depends on whether the tiles themselves are sound and whether there's evidence of movement behind them — our comparison of regrouting versus retiling a bathroom is a useful check before you commit to either.
Material choice is part of the specification, not an afterthought
Porcelain, natural stone, marble and ceramic all behave differently in wet areas — different slip ratings, different sealing requirements, different tolerance for movement — and a tiler should be able to talk you through the trade-offs for your specific room rather than simply installing whatever arrives on site. If you're deciding between finishes, our guide to marble versus porcelain bathroom tiles covers where each performs better and where each needs more ongoing care.
In a mansion block, access is part of the job
Central London tiling jobs often come with constraints that have nothing to do with the tiling itself: lift booking, protected common parts, waste disposal through a shared entrance, and restricted working hours in some boroughs. A tiler who's worked in mansion blocks before will ask about porter access and freeholder rules unprompted; one who hasn't will find out on day one, and the delay lands on your timeline. It's worth checking our notes on porter and access arrangements for mansion block works and, in Westminster specifically, the working hours restrictions that apply, so you can flag them at the quoting stage rather than discovering them mid-job.
A good quote ends with a snagging conversation, not a final invoice
The best sign of a tiler who stands behind their work is that they expect a snagging list — a walk-through at the end where lippage, grout lines, and edge finishes get checked properly before the job is signed off, not after you've moved back in and noticed the joins. If a contractor treats the request for a snagging inspection as an inconvenience, that tells you something about how the middle of the job went too. Our broader snagging list guide is written for full refurbishments but the principle holds just as well for a single tiled room.
What to ask for before you book
- A written, itemised quote per m² that states what's labour and what's materials
- Confirmation of the waterproofing or tanking method for any wet area
- Recent examples of work at your chosen tile size, particularly for large format
- An honest view on whether a full retile is needed, or whether regrouting would do
- Awareness of building access rules if you're in a managed block
- Agreement to a snagging walk-through before the final invoice
If you'd rather skip the vetting process and start from a fixed, published rate, our tiling service page sets out labour pricing by tile size, and you can get a fixed quote or send a photo of the room on WhatsApp for a fast, honest answer on what the job actually needs.