Plumbing Leak Detection
Quick answer
A hidden leak shows up as a water meter that moves with everything off, a stain or soft spot with no source above, mold or a musty smell, or a bill that keeps rising. Plumbers find it with pressure tests, acoustic listening and thermal cameras so only one spot is opened. HomeWyse puts leak detection at about $241–$292 per leak. Call (888) 217-6781 for a plumber in your ZIP.
Follow the short menu, then your 5-digit ZIP. The line goes quiet for a few seconds while it connects; stay on. If it does not connect, call once more: companies taking calls change minute to minute.
Signs you need a plumber
- The water meter moves with every fixture off
- Stains, bubbling paint or soft drywall
- A ceiling stain under a bathroom
- Loose tiles or grout around a shower
- A musty smell from a wall or cabinet
If a stain is spreading or a ceiling is sagging, close the main shutoff and keep people out from under it before you call.
What to check before you call
- Do the meter test: everything off, watch for 15 minutes
- Run only the shower for 10 minutes and look below it
- Check toilets with food coloring in the tank
- Note when the stain or sound appears (after showers, at night, constantly)
What the plumber does
- 1
Isolates the line
Pressure-tests supply lines and flood-tests drains and shower pans to find which one leaks.
- 2
Pinpoints the spot
Uses acoustic listening, moisture meters and thermal imaging through the wall or floor.
- 3
Repairs it
Opens one small area, repairs the pipe, valve or pan, and re-tests.
Leak detection cost
| Job | Typical range | Source |
|---|---|---|
| Leak detection, per leak | About $241–$292 | HomeWyse |
Detection is priced separately from the repair; slab and underground lines cost more to locate. Sources: HomeWyse plumbing leak detection cost (May 2026).
Ready to book a plumber?
One call reaches a plumbing company taking calls in your ZIP.
Follow the short menu, then your 5-digit ZIP. The line goes quiet for a few seconds while it connects; stay on. If it does not connect, call once more: companies taking calls change minute to minute.
Step-by-step guides
Leak in the Wall Behind a Shower: How to Find It and Who to Call
Water behind a shower wall comes from the valve and supply pipes, the drain, or the tile surface. A few simple tests tell you which, and the answer decides whether a plumber, a tile contractor or a restoration company comes first.
Shower Pan Leak: Signs, How to Test It, and the Damage Underneath
When the waterproof layer under a shower floor fails, water goes down instead of into the drain. How to recognize it, test it with an inch of water, and what has to be dried before the rebuild.
Leak detection: common questions
How do plumbers find leaks behind walls?
They pressure-test the lines to confirm which one leaks, then use acoustic listening, moisture meters and thermal cameras to find the spot before opening the wall.
Is my shower leaking through the pan or the valve?
Run the shower aimed away from the walls with the drain plugged (a flood test): a leak below means the pan. A leak only when the valve runs points to the valve or supply pipe.
Can a hidden leak cause mold?
YesDrywall and wood that stay wet for a day or two can start growing mold, which is why finding a hidden leak early matters.
Other plumbing services
(888) 217-6781 is the plumbing line. HearthDry is a referral service; the company you reach is independent.