Bathroom plumbing work and WaterSafe
Moving or adding plumbing (a new shower, relocated toilet) should follow Water Fittings Regulations, the same rules a WaterSafe-registered plumber works to. If your bathroom fitter isn't a registered plumber themselves, ask who does the plumbing side and whether they're WaterSafe registered.
Walk-in showers and wet rooms, what's different
A walk-in shower needs careful floor falls (gradient) toward the drain to work without a shower tray — this is more technically demanding than fitting a standard shower tray and enclosure, and a poorly built one is a common source of water pooling or leaks. A full wet room takes this further, tanking the whole floor.
KBSA and TrustMark, what they actually mean
The KBSA (Kitchen Bathroom Bedroom Specialists Association) is the main UK trade body for the sector, though membership is limited to a few hundred companies nationally, so it's not something every bathroom fitter will have. TrustMark is a broader government-endorsed scheme covering many trades — worth asking which, if either, your fitter holds, rather than assuming either is universal.
Adding a downstairs WC or cloakroom
A ground-floor WC addition usually needs a macerator pump if gravity drainage to the existing waste isn't possible, which adds cost and a small amount of noise compared to a standard gravity-fed toilet. Worth discussing early since it affects where in the house a downstairs WC is practical.
Why waterproofing (tanking) matters
Tanking is a waterproof membrane applied behind tiles, particularly around showers and baths, to stop water getting into the wall or floor structure below. Skipping this step is a common cause of hidden damp and rot that only becomes visible years later — worth confirming it's included, not assumed, in a refit quote.
Understanding the labour vs materials split
Tiles, the suite, and fittings are often a smaller share of the total cost than labour, particularly for a full refit involving tanking and tiling. A cheap quote is worth checking against the same fixture brands and tile spec as competing quotes, not just a lower labour rate.
Underfloor heating in bathrooms
Electric underfloor heating mats are a common bathroom addition since they don't need the full manifold a water-based system does, and work well under tile. They need to be planned before tiling starts and are usually a straightforward add during a full refit rather than a standalone retrofit.
Three steps to hiring the right bathroom fitter
First, ask to see photos of similar completed jobs, ideally local ones. Second, clarify exactly who does the electrical and plumbing work — the fitter directly, or a subcontracted registered tradesperson. Third, get a written quote that separates labour, fixtures and tiling.