Hidden water leaks are among the most damaging plumbing problems a homeowner can face. Unlike a visible dripping tap, a concealed leak inside walls, floors or underground can go undetected for months — causing thousands of pounds of structural damage before it's ever found. Here's what to look for.
Unexplained rise in water bill
A sudden increase in your metered water bill — with no change in household habits — is often the first indicator of a hidden leak. Even a small continuous leak can add £30–£100/month to your bill.
Sound of running water with everything off
If you can hear water moving through your pipes when all taps, appliances and toilets are off, a leak is likely. Try listening at the mains stopcock area or near your water meter.
Damp or wet patches on walls or ceilings
Damp patches — especially those that appear without an obvious cause like rain — suggest a leaking pipe hidden inside the wall or floor above.
Mould or mildew in unexpected places
Mould growing in areas not normally associated with condensation (inside cupboards, behind kitchen units, on internal walls) suggests persistent moisture from a concealed leak.
Discoloured, bubbling or peeling paint
Paint that is bubbling, peeling or stained yellow or brown on walls or ceilings is a classic sign of moisture seeping from a leaking pipe behind the surface.
Reduced water pressure throughout the home
A significant and unexplained drop in water pressure — particularly in multiple locations — can indicate that water is escaping from a leak in the main supply pipework.
Warm or hot patches on the floor
If a section of floor feels warmer than the surrounding area without underfloor heating being installed, a hot water pipe beneath the floor may be leaking.
Water meter spinning with everything off
This is the definitive test. Turn off all taps and appliances, then check your water meter. If the dial is moving, water is escaping somewhere — most likely a hidden leak.
The Water Meter Test
This is the most reliable self-check for a hidden leak:
- 1Turn off all taps, appliances, and the toilet fill valves
- 2Locate your water meter (usually outside near the property boundary, often under a small cover in the pavement)
- 3Note the reading — including the small leak indicator dial if present
- 4Do not use any water for 30 minutes
- 5Check the meter again — if the reading has changed, you have a hidden leak
Hidden Leak FAQs
How do I check my water meter for a leak?
Turn off all taps, appliances and the toilet fill valves. Go to your water meter (usually outside near the property boundary) and check if the small dial or digital counter is moving. Any movement indicates water is escaping somewhere in the system — call us for a leak detection inspection.
How much does leak detection cost in Woking?
A leak detection inspection in Woking typically costs £75–£150 depending on the property size and suspected leak location. If we locate and repair the leak in the same visit, we provide a combined fixed price before starting.
Can a hidden leak damage my home's structure?
Yes — significantly. Prolonged hidden leaks can rot floor joists, damage plasterboard, encourage mould growth, undermine foundations, and cause damage to electrical systems. The longer a leak goes undetected, the more expensive the remediation becomes.
Will my home insurance cover a hidden leak?
Most buildings insurance policies include trace and access cover, which pays for the cost of finding and exposing a hidden leak — though not always the repair itself. We can provide a detailed written report and invoice to support your claim.
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