Internal Cold Mains Leak Detection in Fordingbridge

Symptoms

At a property in BH24, significant standing water was found throughout the utility room, sitting on top of the laminate flooring. Once the flooring was lifted — which sustained damage in the process due to it running beneath the skirting boards — the concrete subfloor below was found to be heavily saturated, indicating water had been present for some time.

The water meter was checked and found to be continuously passing water despite no water being used anywhere in the property. This confirmed an active leak somewhere on the internal supply pipework.

Internal leak detection was clearly required to establish the source and precise location before any remedial work could be planned.

With the concrete floor saturated and no obvious visible pipe failure above ground, the leak could not be pinpointed by visual inspection alone. A structured investigation using pressure testing, tracer gas, and acoustic equipment was needed to identify exactly where on the pipework the failure had occurred.

Methods Used

The investigation began with a pressure test on the internal cold water supply pipework, which confirmed a significant leak was present. Tracer gas was then introduced into the pipework and detection equipment was used to trace its path, identifying the utility room as the area of concern and narrowing the search to beneath the concrete floor.

Acoustic equipment was then deployed to pinpoint the precise location of the leak within that zone.

This methodical approach — pressure testing to confirm a fault, tracer gas to direct the search, and acoustics to pinpoint — is standard practice in internal leak detection when a leak is suspected below a solid floor. It avoids unnecessary excavation by identifying the smallest possible area before any concrete is broken up.

Investigation Process

1. 1
   Arrival and Initial Assessment

   On arrival, the utility room was inspected and substantial standing water was found across the laminate flooring throughout the area.

2. 2
   Flooring Removed

   The laminate flooring was lifted to expose the concrete subfloor beneath, which was found to be fully saturated. The flooring was damaged during removal due to its position under the skirting boards.

3. 3
   Water Meter Checked

   The water meter was located and observed to be continuously passing water with no water in use at the property, confirming an active leak on the internal supply.

4. 4
   Pressure Test Carried Out

   Pressure testing was applied to the internal cold water supply pipework and returned a result indicating a large leak was present on the system.

5. 5
   Tracer Gas Introduced

   Tracer gas was introduced into the pipework and detection equipment was used to trace its escape, directing the search to beneath the concrete floor in the utility room.

6. 6
   Acoustic Equipment Used

   Acoustic equipment was used over the floor surface to listen for the leak signal and identify the specific area where the fault was located.

7. 7
   Concrete Broken Out

   The concrete floor was removed in the identified area, exposing the pipework beneath and revealing the leak at a fitting where the 15mm copper pipe had been damaged.

8. 8
   Repair Carried Out

   A new section of 15mm copper pipework was installed with new fittings. The new pipework was protected and the excavation was backfilled to floor level.

Result & Outcome

Once the concrete was broken out in the area identified by the acoustic equipment, the source of the leak was confirmed to be at a fitting beneath the utility room floor. The 15mm copper pipe attached to the fitting had been damaged, allowing water to escape into the substrate and eventually saturate the concrete slab and flood the floor above.

A new section of 15mm copper pipework was installed with new fittings to replace the failed section. The new pipework was protected and the excavation was backfilled to restore the floor level, completing the repair in the same visit.

For the customer, this internal leak detection investigation meant the leak was found and repaired with a targeted excavation rather than widespread floor removal. The continuous meter movement that had indicated the fault was resolved, and the internal cold water supply was reinstated with the repair confined to the confirmed area beneath the utility room floor.