Can you save money buying tiles through a tiler's trade account?

Yes. Tile retailers offer trade accounts to contractors with discounts of roughly 15 to 25 percent off retail, and most homeowners never know to ask. On a large extension floor, ordering through your tiler's account can save close to a thousand pounds on the same tiles.

What is an uncoupling membrane and is it needed over UFH?

An uncoupling membrane is a thin mat laid between the screed and the tiles that absorbs the small movements of an underfloor-heated floor so they do not crack the grout or de-bond the tiles. Over UFH it is not optional; the tiles will fail without it.

Why should tiles never be dot-and-dabbed over underfloor heating?

Dot-and-dab leaves large voids under each tile sitting over hot air rather than a solid adhesive bed, and the tiles crack as they expand and contract with heating cycles. Solid-bed adhesive across the whole tile is required over UFH floors.

Why order tiles from the same batch?

Tiles from different production batches have slight shade variation that is invisible on paper but clearly visible once laid and impossible to fix afterwards. Ordering one batch, with a waste allowance added, avoids running short and having to mix in a mismatched batch.

When should wall tiles and splashbacks be tiled?

Wall tiling is done after the kitchen units and worktops are in, so the tiler can work to the worktop as a datum and finish cleanly under the wall units. Floor tiling happens earlier, once the screed has passed its moisture test.

Back to Loft Conversion

Phase 7 · Second Fix · Task 05 of 06

Tiling a Loft Conversion: Costs and Trade Accounts

What wall and floor tiling costs, and how buying tiles through your tiler's trade account can cut the bill.

11 min readUpdated 2026Premium

Process infographic showing the five stages of extension floor tiling: screed moisture test, tile order via trade account, membrane installation, tile laying, and grouting, with timeline and cost callouts for each stage

Prerequisites

Complete this first

Plastering

Ask your tiler if they have a trade account before you order a single tile. That one question typically takes around 20% off the retail price of your tiles, which on a typical extension floor is close to a thousand pounds.

Tiling is one of the most visible finishing trades in your build. A completed floor of large-format porcelain on a freshly screeded slab is the moment the space stops looking like a construction site. But the cost is substantial, the timing is rigid, and the technical requirements are tighter than most homeowners realise. Corners cut here are literally underfoot for the life of the building.

What this guide covers

01The Wait: Screed Readiness
02Choosing Your Tiles
03Trade Accounts: The Buying Strategy Nobody Tells You About
04Quantity: Order More Than You Need
05The Uncoupling Membrane
06The Installation Process
07Costs
08Wall Tiles and Splashbacks
09Finding a Tiler
10Sequencing This Trade

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General guidance for homeowners in England (and Wales where we say so), not professional advice. Every site is different: check anything that affects your build with a qualified professional, your local council or building control. Terms

Frequently asked questions

Reference guides for this task

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