Internal Cold Mains Leak Detection in Farnham

Symptoms

The occupant of a property in GU9 had been noticing small amounts of water appearing beneath the kitchen floor. A drainage engineer had already attended and inspected the property but was unable to identify the source.

With no clear explanation for where the water was coming from, internal leak detection was arranged to properly investigate the issue.

Water was visibly coming up through the flooring in the kitchen, which pointed to a leak somewhere beneath the surface. Because the drainage engineer had drawn a blank, there was no working theory about the pipe route or leak location before the engineer arrived.

The cause remained unknown until a systematic detection process was carried out.

Methods Used

The investigation began with a visual check of the water meter, which showed no movement — no active usage was registering at that point. The engineer then worked to determine the pipe routes beneath the kitchen floor and established there were no hot or cold water pipes running under that area.

Pressure testing was then carried out, and within six minutes a drop of approximately one and a half bar was recorded, confirming an active leak somewhere in the system.

With a confirmed pressure loss, tracer gas was introduced into the pipework. Using a gas analyser, readings were detected beneath the kitchen units, narrowing the location significantly.

An endoscope camera was then fed underneath the unit, which revealed a tee piece that was visibly dripping. This combination of equipment is what makes internal leak detection effective in confined, hard-to-access spaces where physical inspection alone cannot reach.

Investigation Process

1. 1
   Visual inspection of water meter

   The engineer started by checking the water meter for any signs of movement or usage. The meter showed no active flow at the time of inspection.

2. 2
   Pipe route assessment

   The engineer worked to determine whether hot or cold water pipes ran beneath the kitchen floor. It was established that no such pipes were present in that area.

3. 3
   Pressure testing carried out

   Pressure testing was applied to the system. Within six minutes, pressure had dropped by approximately one and a half bar, confirming an active leak.

4. 4
   Tracer gas introduced

   Tracer gas was added to the pipework and a gas analyser was used to scan the area. Readings concentrated beneath the kitchen units, pinpointing the zone of interest.

5. 5
   Endoscope camera deployed

   An endoscope camera was fed beneath the kitchen unit. A tee piece was visible on camera and was clearly dripping, confirming the leak source.

6. 6
   Findings presented to customer

   The engineer showed the customer the findings. The customer agreed to remove the shelving units and gave permission for the back of the cupboard to be cut out to access the pipe.

7. 7
   Access gained and repair completed

   The back of the cupboard was cut out, providing clear access to the pipework. The leaking tee piece was repaired using 15mm pipe, a 15mm tee, two 15mm couplings, and pipe inserts.

8. 8
   Post-repair pressure test

   A final pressure test was carried out following the repair. The test confirmed no further leaks were present in the property.

Result & Outcome

The leak was located beneath the kitchen units at a tee piece in the pipework, which was found to be dripping. Access was gained by removing the shelving units and cutting out the back of the cupboard. The repair was completed on the same visit using 15mm pipe, a 15mm tee, two 15mm couplings, and pipe inserts, along with the necessary cutting and cleaning materials.

A post-repair pressure test confirmed the system was holding correctly with no further leaks present anywhere in the property. The precision of the internal leak detection process meant the area of intrusion was kept to a minimum — only the cupboard back required cutting, rather than lifting floor coverings across a wider area.

The customer has been advised to have the back of the cupboard repaired once the area has dried out, and to run a dehumidifier in the property to draw out residual moisture from the floor and surrounding materials.