Within Tolerance
Snagging tape pointing at a gap in the sealant along a shower tray, with water getting in.

Bathroom and en-suite snagging: baths, showers and tiles

The checklistThe detail

In a new-build bathroom, fill the bath and basin to the overflow, run the shower, and flush every toilet. Then check the seals, tiles and grout, and that the extractor fan runs. Look at the bath, basin and shower tray from half a metre for chips. Anything that fails goes on your snag list for the builder.

On the day

19 checks

Do the every-room checks first: Every room. These are the extra checks for each bathroom and en-suite.

Bath, basin and shower

Why and how

Tiles, sealant and fittings

Why and how

If something fails, add it to your snag list and report it to the builder. How to report a snag

Next room: Loft and garage

The detail, for reading before you go

What counts as a snag on a bath, basin or shower tray?

Chips, scratches and damage you can see from half a metre in daylight. NHBC's standards say baths, shower trays and basins should be free of them at handover. In a bathroom with no window, judge by the room's own lights, not a torch.

Report these straight away. NHBC's Buildmark doesn't cover cosmetic damage, such as a chipped bath, reported more than seven days after completion. NHBC's guide to your new home names baths, basins, toilets, shower screens and wall tiling among the things to check on moving-in day.

The official inspection checklist adds that the bath should look level, not move when filled, and drain without gurgling or backing up. Pipes should be hidden unless they are meant to show.

A trick we used we stood in the empty bath before it was filled. A bath that flexes or creaks under your weight is easier to spot then.

How do I check a shower for leaks?

Run it for a few minutes and watch two things: the tray and the seals. Water should drain away without gurgling or backing up. The tray should be firmly fixed, with neat silicone sealant all round, and the screen should be secure and sealed too.

Then look underneath where you can. The LABC Warranty checklist asks about leaks under sinks, sanitary ware and appliances, and says to check the waste pipes as well. Snaggit, which makes a snagging app, suggests laying kitchen roll round the pipe joints. Even a slow drip shows within a few minutes.

A leak you can't stop is an emergency. Call the builder's emergency number rather than adding it to the list. The two-year warranty page covers what counts.

Tiles, grout and silicone: what's acceptable?

Tile joints should be straight and in line, unless the tiles are meant to be irregular. Grout should fill every joint with no holes. Silicone sealant in wet areas should be neat and consistent.

NHBC's standards add some numbers:

  • Next to each other, two tiles shouldn't differ in level by more than 1mm where the joint is up to 6mm wide.
  • Wall joints should be at least 1.5mm wide for ceramic tiles, unless the maker says otherwise.
  • Across a 2m straight edge, the surface shouldn't vary by more than 3mm either way.

Run a finger along each sealant line. It should be smooth and neat, with no blisters or lumps. LABC Warranty's checklist asks for flexible sealant at the corners, and where tiles meet the bath, shower tray and basin.

Tap the tiles gently with a knuckle. Snaggit says a hollow sound suggests the tile isn't properly stuck.

How long should the bathroom fan run?

The checklist asks for the fan to come on with the light, and for it to be switched on at the spur (the separate switch on the wall that powers it). If the fan doesn't run, check that switch first.

Building regulations guidance says an intermittent extract fan (one that switches on and off) in a room with no openable window should keep running for at least 15 minutes after you leave. So in an en-suite with no window, turn the light off and time it.

A trick we used a single sheet of toilet paper held up to the fan grille. If the fan is pulling air, the paper is drawn against it.

Is weak water flow a snag?

It can be. The checklists ask for adequate or satisfactory flow at taps and showers, but give no figure. So compare. Run each tap and the shower in turn, and note any that are clearly weaker than the rest.

Check the waste too. Snaggit says every outlet should drain quickly without pooling. A slow drain in a new house is worth reporting, not living with.

Toilets and towel rails

Flush each toilet and watch it refill. It shouldn't keep running afterwards. The toilet should be firmly fixed, level, with pipes hidden and neat sealant at the base. The seat should be secure, and soft-close where it is meant to be.

A heated towel rail should be firmly fixed and level, with no leaks at the joints, and the wall behind it decorated. Feel it warm up when the heating is on.

Who fixes a leak that appears later?

The builder, in the first two years. NHBC's Buildmark makes the builder responsible for putting right anything that doesn't meet NHBC's standards in that time. The Consumer Code for Home Builders also says the after-sales service should deal with problems with the fixtures and fittings the builder provided. The NHQB lists frequent drips or leaks from taps, showerheads and toilets as a snag.

From our own build

Our en-suite shower panel sat further out at the top than at the bottom.

In both bathrooms, many of the tiles weren't level with each other.

Where this comes from

Every fact on this page comes from the documents below. Anything marked ‘a trick we used’ is our own.

Official and industry guidance

  1. New Homes Quality Board, Pre-Completion Inspection Checklist: House, Version 2, March 2026, p.7, p.7-8, p.8, p.9
  2. NHBC, NHBC Standards 2024, Chapter 9.1: A consistent approach to finishes (copy published by New Build Inspections), 2024, 9.1.7, 9.1.9, 9.1.11
  3. NHBC, New home checklist, January 2017, p.2
  4. LABC Warranty, Snagging checklist for new build homes, undated (PDF metadata January 2016), retrieved 9 October 2026, Kitchens and bathrooms, Wall tiling
  5. NHBC, Buildmark policy booklet (homes registered from 1 April 2025), April 2025, 2.1.1, 2.1.2
  6. NHBC, Guide to your new home, November 2025, p.6
  7. New Homes Quality Board, A homeowner guide to snagging, May 2026, Emergencies that require immediate attention, Other possible snags and defects
  8. Ministry of Housing, Communities and Local Government, Approved Document F: Ventilation, Volume 1: Dwellings, 2021 edition, 2021 edition, in effect from 15 June 2022, 1.51
  9. Consumer Code for Home Builders, Code requirements and good practice guidance, fifth edition, January 2024, 5.1.2

Snagging firms and buyer guides

  1. Snaggit, The complete new build snagging checklist (2026), 2 April 2026, Bathroom(s)
  2. Snaggit, How to do a snagging inspection: step-by-step guide, 16 April 2026, Step 5

Last checked 15 October 2026

For general education only. It isn't legal or surveying advice. Always check your own warranty documents and Code version, and speak to your housebuilder, your warranty provider or a qualified snagging inspector before relying on it. Read the disclaimer.