repairs
Leak detection and repair
A non-invasive leak detection survey costs £250 to £600 and finds the leak without taking a floor up. Most buildings insurance policies cover this under a trace and access clause, which is worth checking before paying for it yourself.
What this covers
Typical price. £250 to £600 for a detection survey
What the job covers
- Tracing leaks under floors and behind walls
- Thermal imaging and acoustic detection
- Repairing failed joints and pinholes
- Shower tray and seal leaks that look like plumbing
- Reports for insurance trace and access claims
What is involved
Finding a leak is a different skill from fixing one. A specialist uses thermal imaging to see the temperature difference a leaking hot pipe creates through a floor, acoustic equipment to hear the escape of pressurised water, tracer gas pushed into a drained pipe and sniffed at the surface, and moisture meters to map how far the water has travelled. That last point matters, because water runs along joists and appears in a room that has nothing to do with the failed pipe.
A good proportion of suspected plumbing leaks are not plumbing. A shower tray whose seal has failed, a bath with a perished waste washer, grout that has opened up in a wet area, or a roof or window defect will all produce a wet ceiling below. A survey that starts by ruling those out saves lifting a floor for nothing.
On heating systems, the tell is pressure. A sealed system that needs topping up every few weeks is losing water somewhere, and the loss is often at a radiator valve gland or a compression joint under a floor. On mains supply, a leak between the meter and the house shows as a meter that turns with every tap in the house shut off, and that section of pipe is usually the homeowner's responsibility.
Tracing leaks under floors and behind walls, one of the jobs a leak detection specialist is hired for.
Choosing someone for the job
Check your buildings insurance for trace and access cover before booking, and ask the firm whether they produce insurer-ready reports. Ask which detection methods they carry, because thermal imaging alone will not find a cold water leak in an uninsulated void. Ask whether the quoted price includes the repair or detection only.
Common questions
Does insurance pay for leak detection?
Most buildings policies include trace and access cover, typically to a few thousand pounds, which pays to find the leak and make good afterwards. The repair to the pipe itself is usually excluded.
How do I know if I have a hidden leak?
Turn every tap and appliance off and watch the water meter for half an hour. If it moves, water is going somewhere. On a heating system, pressure that falls week after week is the equivalent sign.