Internal Cold Mains Leak Detection in Nottingham

Symptoms

When the internal stopcock was isolated, the noise stopped entirely — confirming that the source was internal to the property rather than on the mains supply outside. A pressure test on the cold pipe gave a small but measurable drop, providing further confirmation that a leak existed somewhere within the internal pipework.

Despite these indicators, no water was visible at any point, making this a concealed leak requiring methodical investigation.

Methods Used

Acoustic equipment was used across the property to attempt to pinpoint the leak by sound, but the noise proved continuous throughout — making isolation by acoustics alone impractical. A damp meter was used across the utility room floor and returned very high readings throughout, confirming significant moisture in the substrate but further complicating precise location.

Given the evidence gathered, this internal leak detection job required the floor to be lifted to locate and access the leak directly. Once lifting began, wet material was found beneath the floor, and by continuing to expose the area the exact point of the leak was reached and repaired.

A final pressure test confirmed no further leaks remained in the property.

Investigation Process

1. 1
   Stopcock Isolation Test

   The internal stopcock was closed to check whether the continuous pipework noise would stop. It did, confirming the leak was internal to the property.

2. 2
   Pressure Test

   A pressure test was carried out on the cold pipe, which showed a small drop — providing measured confirmation of an active internal leak.

3. 3
   Tracer Gas Introduced

   Tracer gas was fed into the pipework and readings were taken across the property. A large concentration of gas was found in the downstairs utility room, with the highest readings beneath the utility sink.

4. 4
   Cupboard Opened and Pipework Exposed

   With the customer's permission, part of the back of the utility sink cupboard was removed and the area around the pipework was broken out. Green pipework was visible but there was still no visible water.

5. 5
   Acoustic Survey Conducted

   Acoustic equipment was used throughout the property to attempt to locate the leak by sound, but the noise was continuous across all areas and could not be used to isolate a single point.

6. 6
   Damp Meter Survey of Utility Room

   A damp meter was used across the utility room floor and returned very high readings throughout, confirming moisture was present beneath the surface but making precise pinpointing difficult.

7. 7
   Floor Lifted in Utility Room

   With the customer's agreement, the utility room floor was lifted. Wet material was found beneath it, and continuing to expose the area led directly to the location of the leak.

8. 8
   Leak Located and Repaired

   The leak was accessed and repaired using copper pipe, copper fittings, and soldering equipment. The area was cleaned and made good following the repair.

9. 9
   Final Pressure Test

   A pressure test was conducted after the repair and confirmed there were no further leaks present anywhere in the property.

Result & Outcome

The result of this internal leak detection work was a confirmed repair with no residual issues detected. The customer can now proceed with confidence knowing the source of the noise and the concealed leak have both been fully resolved. The engineer has recommended that the customer submit this report to their insurance company as a record of the investigation and repair.