Bathroom Leak Detection in London
A bathroom leak survey works through five possible sources in turn: the bath, the shower tray or enclosure, the waste pipes, the supply pipes and the tiled surfaces. Each source has a test that rules it in or out, so the visit ends with a located leak or a source that has been eliminated.
What the visit covers
- A visual and moisture check of the bath, tray, enclosure, basin, toilet and the walls and floor around them
- A fill, spill and run sequence that exercises each fitting separately while the room below or behind is watched
- A pressure test of the hot and cold supply to the bathroom, isolated from the rest of the house
- Dye in the waste water where a waste joint is suspected, followed by an endoscope look where a small opening allows
- A written report of what was found and where, and which sources were ruled out
Published prices
What it costs
- Fixed-price leak location package
- The package gives one fixed price, known before the visit, to locate a leak in one property using whichever methods the leak needs.
- £580Fixed price
Or by the hour
- Standard leak detection
- General water leak detection in a property.
- £180an hour
- Moisture mapping
- Mapping moisture to find where water is travelling.
- £180an hour
No VAT is charged
A fixed hourly rate that cannot rise on the day
No find, no fee applies when a live leak inside your own property cannot be located. No find, no fee in full
Order of work
Walk the room and the room below
The team looks at where the water shows (ceiling, skirting, wall, floor) and at the bathroom above or beside it, with a moisture meter, before any fitting is touched. The stain is rarely under the fault, so the pattern matters more than the spot.
Test each source on its own
The supply is isolated and pressure tested. The bath, tray and basin are then filled, spilled and drained one at a time, with the toilet flushed last. The order is set by what the first readings show, as laid out in the checklist below.
Look inside before opening up
Where a test points at a hidden joint, an endoscope or a small access opening shows it. The report records the reading, the test that produced it and the position, so any opening up is kept small. See how a report reads.
How a bathroom survey is organised
A bathroom has more than a dozen places that can leak, but only five kinds of source. Treating them as five checklists, each with its own proof, stops a survey turning into guesswork or into lifting every tile. A wet room with no tray works the same way but searches the whole floor, as wet room leaking explains.
The sources and the test that clears each one are in the table. A test clears a source only when the damp stops behaving in the way it did before, or when a reading stays flat while the fitting is working.
| Source | What it looks like | The test that clears it |
|---|---|---|
| Bath | Stain on the ceiling below or on the panel, worse after a bath is taken | Fill to the overflow and hold it, then drain, watching the room below and the void |
| Shower tray or enclosure | Damp at the tray edge or the skirting outside the screen | Spill test on the seal, then a run test with the screen closed, then a waste test |
| Waste pipes | Damp only after water is emptied, often a smell | Dye in the water, drain it, then look at the joint with an endoscope |
| Supply pipes | Damp that continues with every tap off | Isolate the bathroom supply and watch a pressure gauge |
| Tiles and grout | Hollow tiles, discoloured grout, a wall damp near a shower | Moisture readings across a grid, before and after the shower has run |
What each method adds
Moisture meters and mapping show where damp has gone and how far it has spread. They cannot say where it started. Moisture mapping is used first for that reason: it tells the team which wall or floor area to test next.
A pressure test is the cleanest way to separate a supply leak from everything else, because it ignores spills and waste. It cannot see a waste leak or a failed seal, which only leak when water is used.
Dye and an endoscope inspection through a small opening cover the waste side. Thermal imaging is added where a supply pipe or a heated floor loop is suspected, though it is not reliable on a wall that has just been wet by a shower.
If water is running near electrics or a pipe is actively flooding, turn off the water at the stop tap and, if you can reach it without standing in water, the electricity at the consumer unit. Keep clear of wet sockets and light fittings.
What a bathroom survey costs
For one bathroom or flat, the £580 package follows the leak from tray, bath and waste to the hidden supply under a single price that is known before the visit. No VAT is charged.
Hourly work is charged at £180 an hour, which is a fixed hourly rate that cannot rise on the day, or £180 an hour for a moisture mapping survey, a starting rate. No VAT is charged. A detailed comparison of the two routes is in package or hourly rate.
No find, no fee applies when a live leak inside your own property cannot be located. A leak that belongs to a neighbour or to a communal pipe is a located leak and is charged, and so is a survey that establishes there is no leak. Full terms are on the no find, no fee page.
A stain on the ceiling below a bathroom can lead to an escape of water claim. Cover depends on the policy and the insurer decides; the claim steps are set out in order.
What the survey cannot do
The visit locates the leak and the report names what needs doing. A small repair, such as tightening a fitting or replacing a small part on the pipe, can be done on the same visit once the leak is found, agreed with you first. A larger repair is quoted before any work starts, and the leak is stopped in the meantime. Re-tiling a wall or making good a ceiling is separate: damage to walls, ceilings and finishes is quoted by a partner team of builders and decorators, who give a price for each job. See leak repair after detection and leak damage repair and remediation.
A slow leak that only shows after a long soak, such as a failed seal behind a bath that is used twice a week, can need a second look after the room has been used. When a source cannot be proven in one visit, the report says which sources were cleared and which remain. How accurate leak detection is explains the zones and marks a report uses when the readings are unsure.
Water from a neighbouring flat or from outside through the wall can look like a bathroom leak. A moisture pattern that follows the wall rather than the fittings points that way, and the report records it.
Questions customers ask
How long does a bathroom leak survey take?
The length is set by how many sources have to be cleared and how long the bath and tray take to drain between tests. Each source is tested separately, so a room with one fitting is quicker than one with a bath, a separate tray and a wall-hung toilet. How long a leak detection survey takes lists what sets it.
Will you remove the bath panel or tiles?
A clip-on bath panel comes off to look at the void, and nothing else is opened until a test points at it. Tiles are left in place wherever a moisture reading or an endoscope can answer the question first.
Can you tell if the leak is from the flat above?
Often yes. A supply test on your own pipes that holds steady, with damp that continues, points away from your bathroom. Where the source proves to be a neighbour or a communal pipe it is a located leak and the survey is charged. No find, no fee applies when a live leak inside your own property cannot be located.
How much does bathroom leak detection cost?
The package is £580 for a bathroom leak inside one property, with the methods chosen on the day. Hourly work is £180 an hour. No VAT is charged. The wider market picture is in the cost guide.
Do I need to stop using the bathroom first?
Use it as normal until the visit, and note when the damp worsens: after a bath, after a shower, or at random. That pattern is the first clue. If a ceiling is bowing or water is near electrics, stop using the room and turn the water off. How to prepare for a leak detection visit lists what to clear and note.