Water Mains Leak Detection in Wokingham

Symptoms

A property in RG40 was showing clear signs of a water leak, with damp found throughout the kitchen floor and water damage to the lower 300mm of the walls. The laminate flooring was wet on arrival, pointing to an ongoing leak that had been present long enough to cause visible structural damage to the surrounding surfaces.

The water meter confirmed continuous usage with no water being drawn deliberately, and closing the internal stopvalve brought the meter to a halt. This isolated the source to the internal pipework rather than any external supply.

Internal leak detection was the appropriate course of action given the confined, finished nature of the kitchen environment and the need to pinpoint the fault before any unnecessary excavation.

Methods Used

Before any intrusive work was carried out, the hot water and heating system was isolated — an isolation valve was fitted on the supply to the feed and expansion cistern and the cold water storage cistern — so that the internal mains supply pipework could be tested in isolation. The pipework was then charged with tracer gas and a systematic sweep of the kitchen was carried out to identify where the gas was escaping.

Internal leak detection in a property with finished flooring and wall linings requires a methodical approach to avoid unnecessary disruption. Acoustic correlation and a damp meter helped narrow the area of interest before the tracer gas pinpointed the specific location, allowing excavation to be targeted rather than exploratory.

Investigation Process

1. 1
   Initial assessment

   On arrival, the kitchen laminate floor was found to be wet and the lower 300mm of the walls showed water damage. The water meter was registering continuous usage.

2. 2
   Stopvalve isolation test

   The internal stopvalve was closed and the meter usage stopped, confirming the leak was within the internal pipework rather than the external supply.

3. 3
   System isolation

   Isolation valves were fitted to the supply lines serving the feed and expansion cistern and the cold water storage cistern, taking the hot water and heating system out of the equation and leaving the mains supply pipework ready for testing.

4. 4
   Tracer gas pressure test

   The internal mains supply pipework was charged with tracer gas. A leak was confirmed, and the gas was detected at the right-hand wall of the kitchen.

5. 5
   Excavation and leak found

   The area at the right-hand wall was excavated, exposing a leaking section of pipework that supplies the kitchen sink.

6. 6
   Repair carried out

   The leaking section was cut out and renewed using a 15mm coupling, a 15mm isolation valve, and 1 metre of 15mm tube.

7. 7
   Post-repair pressure test

   The repaired mains was pressure tested at 3 bar for 30 minutes with no loss of pressure recorded, confirming the repair was sound.

8. 8
   Reinstatement

   The water supply was reinstated and the pipework was flushed through to clear any residual tracer gas or debris.

Result & Outcome

The leak was located at the right-hand wall of the kitchen, where a section of pipework supplying the kitchen sink had failed. Tracer gas detection identified the precise point, meaning excavation was limited to the area that needed it rather than speculative opening-up of the floor across a wider zone.

The damaged section was cut out and replaced with new 15mm pipework, fittings, and an isolation valve. A 30-minute pressure test at 3 bar with no pressure drop confirmed the integrity of the repair before the supply was restored.

For a property in RG40 with this level of floor and wall damage, a precise internal leak detection outcome like this matters — the leak source was confirmed, the repair was contained to a defined area, and the installation was verified under pressure before work was signed off.