Leak detection is the process of finding where water escapes a pipe without tearing out walls to look. Active leaks are an emergency. If water is spreading or the meter keeps turning with every fixture off, close the main valve and call our 24/7 line. We schedule same-day and after-hours leak checks when a plumber is available.
Slow leaks are quieter and cost more over time. A pinhole that weeps for six months can soak insulation, lift flooring and feed mold behind the wall. Finding it early limits the repair to a few square feet.
When a hidden leak is an emergency
Call at once if you hear water running with everything off, see a wet patch growing on a ceiling or floor, or find warm spots on a slab. A hot spot on the floor can mean a hot water line is leaking beneath it.
Close the main valve to stop the loss. If the house is still without a break in the leak, open a low tap to drain the lines and call us. Most hidden leaks can wait a few hours for a plumber once the main is closed, which is why we start with a controlled shutoff.
Is the leak inside the house or outside?
Start with the water meter. Turn off every fixture and look at the leak indicator, the small triangle or dial that spins when water flows. Movement means water is leaving somewhere. Then close the main valve to the house. If the indicator stops, the leak is inside. If it keeps moving, the leak is between the meter and the house.
Your water bill carries the same clue. Helix Water District supplies Lemon Grove, so a jump on your bill with no change in habits is a reason to run this test. We can do it for you in a few minutes.
How we find a leak
Meter and pressure test
We isolate the supply line and watch for pressure loss to learn whether the leak is on the supply side.
Acoustic listening
Sensitive ground and wall microphones pick up the sound of water escaping a pressurized pipe.
Thermal imaging
An infrared camera shows temperature differences from a leaking hot line or wet material.
Moisture mapping
A moisture meter marks the edges of the wet area so we cut only where needed.
Want the exact spot found?
Call to book leak detection for your home.
Signs of a hidden leak
Higher bills
A rise with no change in habits is the earliest warning, and the easiest to check.
Musty smell
Odor without visible water suggests moisture behind a wall or under a floor.
Bubbling paint
Wall paint that blisters or peels from the inside often sits over a wet cavity.
Low pressure
A leak on the supply line can lower pressure at fixtures.
Detection methods compared
| Method | Best for | Limit |
|---|---|---|
| Meter test | Deciding if the leak is inside or outside | Does not pinpoint the spot |
| Acoustic listening | Pressurized pipes in slabs and walls | Noisy sites can mask the sound |
| Thermal imaging | Hot water lines and wet materials | Shows temperature, not water directly |
| Camera inspection | Drain and sewer line leaks | Needs access through a cleanout |
What leak detection costs
Insurance may cover water damage but not the pipe repair or the search for a slow leak. Keep your water bills, because they show when the leak began.
Codes, permits and licensing
Work on leak detection in California is governed by the California Plumbing Code, a state version of the Uniform Plumbing Code (UPC). Whether a permit applies depends on the scope, so ask the City of Lemon Grove building department or ask us before work begins.
Plumbing contractors in California hold a C-36 license from the Contractors State License Board, and you can check any license at cslb.ca.gov.
Frequently asked questions about leak detection in Lemon Grove
Yes. Call the 24/7 line, close the main valve and we schedule the first available plumber for an active leak.
Turn off all fixtures, find the meter and watch the leak indicator or dial. If it moves, water is going somewhere.
Mostly yes. Acoustic and thermal tools narrow the search so we only open the wall at the exact spot.
Yes. A camera inspection checks drain and sewer lines. See sewer camera inspection.
We locate it first, then talk through a spot repair or a reroute. Details are on our slab leak repair page.