A hidden water leak rarely announces itself all at once. It usually shows up first as a small, easy-to-dismiss change — and catching that change early is the difference between a simple repair and a much larger one.
Start with the water bill
The most common first signal is a water bill that's climbed without a clear reason — no new appliance, no extra household members, no obvious change in habits. A one-time bump can be a fluke. A bill that stays elevated over two or more billing cycles is worth investigating further.
Check the meter with everything off
Turn off every fixture and water-using appliance in the property, then check the water meter. Most meters have a small dial or digital indicator that moves when water is flowing. If it's still moving with everything off, water is going somewhere in the system, even if you can't see where yet.
Look for physical signs
A few things are worth a walk-through of the property:
- Warm or unusually damp patches of flooring, which can point to a leaking hot-water line.
- Staining, bubbling, or peeling paint on walls or ceilings.
- A musty smell in a room with no obvious source.
- Unusually soggy or green patches in the yard, away from any sprinkler head.
- The sound of running water when nothing is turned on.
When it's time to call someone
If you've confirmed the meter is moving with everything off, or you're seeing two or more of the signs above without an explanation, that's typically the point where a professional leak detection can narrow things down faster than continued guessing — particularly for leaks that aren't visible, like those below a slab or inside a wall.