The leaks that cause the most damage are rarely the dramatic ones. A burst pipe gets noticed in seconds. A pinhole in a supply line behind the bathroom wall can drip quietly for months, soaking plaster, rotting timber and feeding mould long before anyone sees a puddle. The good news is that hidden leaks almost always leave clues. If you know what to look for, you can call for leak detection while the repair is still small.
1. Your water bill climbs without a reason
Compare your last few bills. If usage rises steadily while your habits have not changed, water is going somewhere it should not. A running toilet or dripping tap can explain a small rise, but a sustained jump usually points to a leak on the pressurised supply side of your plumbing.
2. The water meter moves when every tap is off
This is the simplest test you can do yourself. Turn off every tap, appliance and fixture, note the meter reading, and check it again after an hour without using any water. If the reading has changed, there is a leak somewhere between the meter and your fixtures. It does not tell you where, but it confirms the problem is real and worth a professional inspection.
3. Stains, bubbling paint or soft plaster
Yellow or brown rings on a ceiling, paint that blisters or peels, and plaster that feels soft or crumbly are classic signs of water travelling inside a wall or slab. Keep in mind that water follows gravity and pipe runs, so the stain is often some distance from the actual leak. Opening the wall where the stain appears is a common and costly mistake.
4. A musty smell that will not go away
A persistent damp, earthy smell in a cupboard, under a sink or in one corner of a room usually means moisture is trapped somewhere it cannot dry. Mould needs only a day or two of constant moisture to start growing, so treat an unexplained smell as an early warning rather than a cleaning problem.
5. Low or uneven water pressure
If one fixture suddenly delivers a weaker flow while the others are normal, the problem may be a blockage or a faulty cartridge. If pressure drops throughout the property, a leak on a main supply line is a strong possibility, especially when it comes with any of the other signs on this list.
6. The sound of running water when nothing is running
Late at night, when the property is quiet, listen near walls and floors where pipes run. A faint hiss or trickle with every tap closed is one of the clearest signs of a pressurised leak. Our acoustic detection equipment works on the same principle, only far more sensitively.
7. Warm patches on the floor
A warm spot on a tiled or concrete floor can indicate a leak on a hot water line running underneath. Hot water leaks waste energy as well as water, and they can damage flooring adhesive and screed over time. Thermal imaging is very effective at confirming this kind of leak without breaking the floor.
What to do if you notice these signs
- Run the meter test above and write down the readings.
- Take photos of any stains, damp patches or damage, with a date.
- Locate your main shut-off valve so you can isolate the supply quickly if the leak gets worse.
- Avoid cutting into walls or floors to search for the source yourself.
- Book a professional leak detection visit so the exact point can be found before any repair work starts.
Finding the precise source first is what keeps a leak repair small, tidy and affordable. If you have spotted one or more of these signs, our leak detection service uses non-invasive methods to pinpoint the problem, and we explain exactly what we found before recommending any repair.