0333 567 2639

Concrete slab

Hot water pipe leaking under a utility room slab, Grimsby

The kitchen floor was saturated. Thermal imaging marked two areas, an air test showed the pipe held nothing, and opening the utility room slab found a corroded pipe.

FLIR thermal camera showing a warm band where a hot pipe runs under the floor
Thermal imaging over the utility room floor, Grimsby job.
Location
Grimsby, Lincolnshire (DN33)
Property
Large semi-detached house
System
Hot and cold copper pipes buried in concrete floors
First sign
Hot water pipe from under the boiler leaking; very high moisture in the kitchen floor
Engineer
Robert Gires, ADI Leak Detection
Outcome
Leak found under the slab; repaired in copper; re-pipe recommended

What was happening

The hot water pipe running from under the boiler had developed a leak, raising concern about water getting into the kitchen floor and the utility room behind the washing machine.

The pipes run under concrete floors, so nothing could be seen.

How the leak was traced

  1. Thermal imaging

    Traced the hot water pipe route and showed two areas of concern: behind the washing machine in the utility room, and the kitchen floor.

  2. Damp meter

    Very high readings in the kitchen floor.

  3. Air pressure test

    A compressor on the hot water pipework showed it could not hold any pressure: a substantial failure, not a small seep.

  4. Visual inspection

    After opening up, both the hot and cold pipes could be seen.

What was found

Under the kitchen unit both the hot and cold pipes were in very poor condition.

The active leak was on the hot water pipe under the utility room slab.

What happened next

The damaged section was cut out and replaced in copper.

Because of the state of both pipes, the engineer recommended replacing the pipework, since further failures are likely.

What else the floor tells you

Opening a slab shows the condition of the pipes as well as the leak. Here it told the owner the repair would not be the last one unless the old pipework was replaced.

Leaks under concrete and screed: the full guide.

Photos from the job

  • Damp meter displaying 999, its highest reading, over a kitchen floor
    Damp meter at the top of its scale on the kitchen floor.
  • Two pressure gauges on a hose rig laid on the kitchen floor
    Pressure testing the hot water pipework.
  • Corroded pipes exposed in a channel in the concrete floor
    Corroded pipework exposed under the slab.
  • Close-up of a corroded green copper tee with a pinhole
    Corrosion and a pinhole on the removed copper.
  • New copper pipe and elbow fitted in an opened hole by the wall
    New copper fitted in the utility room.

Case published by ADI Leak Detection. Photos taken by the engineer during the investigation.

Similar jobs

All case studies

  • Burpham, Surrey. Underfloor heating, Concrete slab

    Boiler losing pressure within the hour, water at the skirting

    Water was rising through gaps in the living room floor. Three methods agreed on one spot, a few tiles were lifted, and a push-fit coupler had slid off the plastic heating pipe.

    Leak found; joint remade with crimped fittings; pressure held

  • Torquay, Devon. Concrete slab

    Topping up the heating every three hours

    Pipes to a radiator that had been removed years before were still live under the kitchen. The cold feed had also worn through where it rubbed against them.

    Two leaks found and repaired; pipes protected

Call 0333 567 2639

Mon to Fri, 7:30am to 6:30pm