How to Find a Water Leak

Hidden leaks, inside walls, under floors or underground, are notoriously hard to spot until they've caused noticeable damage. A few simple checks can help confirm whether you have a leak before you call a plumber.

Check your water meter

Turn off every tap and water-using appliance in the house, then check your water meter. If the meter keeps moving with everything off, water is escaping somewhere in the system. Note the reading, wait an hour without using any water, and check again for confirmation.

Watch your water bill

An unexplained jump in your water bill, without a change in household water use, is one of the more reliable early signs of a leak, particularly an underground or slab leak that isn't visible.

Look for damp patches and mould

Check walls, ceilings and skirting boards for damp patches, discolouration, peeling paint or a musty smell, especially in areas near bathrooms, kitchens or laundries where pipework runs close to the surface.

Listen for running water

With everything else quiet, listen near walls and floors for a faint hissing or trickling sound, which can indicate a pressurised leak inside a wall cavity or under a slab.

Check outdoor areas

Unusually lush or soggy patches of lawn, or water pooling in the yard without an obvious cause like rain or irrigation, can point to an underground pipe leak.

When to call a professional

If your meter test confirms a leak but you can't locate it visually, professional leak detection using pressure testing or acoustic equipment is usually the next step, particularly for leaks under a slab or underground, which are very difficult to pinpoint without the right tools.