How much does central heating leak detection cost?
At Leak Detect London, a central heating leak survey starts from £150. What you pay beyond that depends mainly on which detection methods the job needs and how much of the property has to be surveyed. A small flat where the leak shows up clearly on a thermal camera sits at the lower end. A house with pipes buried in concrete across several rooms, where thermal imaging has to be backed up with acoustic listening or tracer gas, costs more.
Across the UK, prices for this kind of work vary between firms and regions, and they are often quoted in different ways: some firms charge a fixed survey fee, some charge by the hour, and some add the report as an extra. When comparing quotes, check what the figure actually covers. Our general London leak detection costs guide covers all types of leak. This article deals with heating systems specifically.
What are the prices for each type of heating leak survey?
These are our published prices. All include VAT and the written report, and the exact figure is agreed before any work starts.
| Survey | Price | Typical heating use |
|---|---|---|
| Thermal imaging survey | £150 to £250 | Radiator circuits, visible pipe routes, heating pipes in walls or shallow screed |
| Acoustic leak detection | £150 to £300 | Pinpointing along a known pipe under a solid floor |
| Tracer gas testing | £200 to £350 | Deep or slow leaks, plastic pipe, floors where thermal imaging is unclear |
| Combined detection package | £250 to £500 | Heating leaks that need more than one method to confirm |
| Under-floor leak detection | £300 to £700 | Underfloor heating and heating pipes buried in concrete floors |
| Emergency detection (24/7) | £300 to £500 | Active leaks causing damage, evenings, weekends and bank holidays |
Our pricing page lists every service, including the survey types above.
What affects the price of a central heating leak survey?
- The detection methods needed. Many heating leaks show on a thermal camera once the system is hot. If the image is unclear, acoustic equipment or tracer gas adds time and equipment, and tracer gas means draining and refilling the affected circuit.
- How much of the system is involved. A single radiator circuit is quicker to survey than a whole house with several zones, or a system with both radiators and underfloor heating.
- Where the pipes run. Pipes in walls and under timber floors are usually quicker to trace than pipes deep in a concrete slab under a thick floor finish.
- Whether the system can be isolated. Working isolation valves let the engineer test sections one at a time. Seized or missing valves make that slower.
- Timing. Out-of-hours and urgent attendance is priced as emergency detection.
- Access. Clear access to the boiler, manifold, radiators and floors keeps the visit efficient. Heavy furniture over the suspect area, or a fully fitted kitchen over the pipe route, adds time.
Why is leak detection priced differently from a plumber's call-out?
A heating engineer or plumber called out for pressure loss will typically check the boiler, the relief valve, the expansion vessel and anything visible. That is exactly the right first step. What they are less likely to carry is the survey equipment to find a leak inside a floor or wall, so if the obvious checks come up clean, the options are often to keep topping up or to start lifting floorboards and tiles where a leak seems likely.
A leak detection survey is priced around a result: a marked leak position with evidence of how it was found. Exploratory opening-up tends to cost more once making good is included, especially on tiled or screeded floors, and it can still miss. That is the comparison worth making when you look at the survey fee.
What does the survey price include?
Our prices include the engineer's visit, all detection equipment used on the job, and a written report with thermal images, photographs and a description of the leak location and recommended repair. The report is written so it can support a trace and access insurance claim. Surveys are carried out on a no find, no fee basis. If the scope needs to change during the visit, for example because a second leak appears on a different circuit, the engineer explains and agrees a new figure before carrying on.
Our central heating leak detection page explains how the survey itself runs, from pressure checks to pinpointing.
What costs come after the leak has been found?
The survey tells you where the leak is. The overall bill also includes the work that follows, and it helps to plan for it:
- The repair. Usually carried out by a heating engineer or plumber. A repair at a single point is normally simpler than rerouting or replacing a pipe run.
- Opening up and making good. Lifting and relaying tiles or boards, breaking out and reinstating screed, and replastering if the pipe is in a wall.
- Drying. Screed and masonry that have been wet for a long time may need drying before new flooring goes down.
- System care. After a leak repair, refilling with fresh water and inhibitor is good practice, and a heavily contaminated system may need cleaning.
These costs depend heavily on the building and the finishes, so they are best priced by the contractors once the leak position is known. A precise location is what keeps them down.
Does home insurance cover central heating leak detection?
Many buildings insurance policies include trace and access cover, which pays towards finding the source of an escape of water and opening up and reinstating the structure to reach it. Some policies include it as standard and some only with an add-on, limits and excesses vary, and some policies do not pay to repair the leaking pipe or fitting itself. Read your policy, and contact your insurer before any opening-up work if you intend to claim.
Insurers generally expect evidence of where the leak is and how it was found. Our survey report is written with that in mind.
How can you keep the cost of a heating leak survey down?
- Log the pressure. Note the cold boiler pressure at the same time each day for a week. It shows how fast the loss is and whether it is steady.
- Rule out the boiler. Check whether the relief valve discharge pipe outside is wet. If it is, a Gas Safe engineer should look at the boiler first. Our guide to a boiler that keeps losing pressure explains the checks.
- Note what you have seen. Warm spots on the floor, damp skirting, ceiling marks, and which rooms have pipes going into the floor.
- Keep the system running. Top up to the correct cold pressure before the visit so the heating can run at temperature for the thermal survey.
- Clear access. Move rugs and furniture from the suspect area and make sure the boiler, radiator valves and any manifold can be reached.
- Have your policy to hand. If you plan to claim, check with your insurer first so the report covers what they need.
When should you call a leak detection specialist?
If the boiler and relief valve have been checked and the pressure still falls, or you have damp or a warm patch that points to a hidden leak, a survey is usually cheaper than guessing. If water is actively coming through a ceiling or floor, isolate the heating, switch the boiler off and call for emergency detection. Call 020 3912 0200 for a fixed price for your property.
Frequently asked questions
How much does central heating leak detection cost in the UK?
Prices vary between firms and depend on the methods and area involved. At Leak Detect London, surveys start from £150 for thermal imaging, with a combined thermal, acoustic and tracer gas package at £250 to £500 and under-floor surveys at £300 to £700.
Is central heating leak detection worth the cost?
Where a leak is hidden, a survey that marks the position usually costs less than exploratory opening-up and the making good that follows, and it gives you evidence for an insurance claim.
Does the survey price include the repair?
No. The survey locates and documents the leak. The repair is carried out afterwards, usually by a heating engineer or plumber, and priced separately.
Will my insurer pay for leak detection?
Many buildings policies include trace and access cover for finding an escape of water, but not all do, and terms vary. Check your policy and speak to your insurer before work starts.
What happens if the leak is not found?
Our surveys are carried out on a no find, no fee basis, so you do not pay the survey fee if the leak is not located.
