Leak Detection Service — Find Hidden Water Leaks

A leak you cannot see can run for weeks, soaking framing, flooring, and insulation before it shows up as a stain or a bill. Finding the exact spot first is what keeps the repair small.

Signs of a Hidden Leak

• A water bill that rises with no change in how you use water
• The sound of running or dripping water when every fixture is off
• Damp, bubbling, or discolored paint, drywall, or ceilings
• Musty smells, mold spots, or warped flooring
• Warm spots on the floor or hot water that runs out quickly
• Low water pressure in one area or across the house
• A water meter that keeps moving while everything is turned off

A Simple Check You Can Do First

Turn off every faucet and appliance that uses water, then look at your water meter. If the leak indicator or the small dial keeps moving, water is going somewhere. If it stays still, the problem may be a fixture, a toilet that is running quietly, or something else that is easier to fix. This check does not locate the leak, but it tells you whether to book a detection visit.

How Plumbers Find Leaks

Method	What it finds	Best for
Pressure test	Confirms a leak exists in a section of pipe	Deciding where to look first
Acoustic listening	The sound of water escaping a pressurized pipe	Slab, wall, and underground leaks
Thermal imaging	Temperature differences caused by moving water	Hot-water lines and wet insulation
Moisture meter	Hidden dampness in walls, floors, and ceilings	Tracing how far water has spread
Camera inspection	Cracks and breaks inside drain and sewer lines	Drain-side leaks and root damage

What a Leak Detection Visit Usually Includes

• A conversation about the signs you have seen and when they started
• A meter check and a pressure test to confirm the leak
• Listening and imaging to narrow down the location
• Marking the likely spot, and a plain explanation of what was found
• A written estimate for the repair, with the option to say no

What Can Go Wrong

• More than one leak: fixing the first can reveal a second, so a second pressure test after the repair is worth asking about.
• Noise and interference: traffic, plastic pipe, and loud appliances can make a leak harder to hear, which is why plumbers combine methods.
• A test opening may still be needed: detection narrows the spot, but confirming a leak behind a finished wall can still require a small opening.
• Water already spread: by the time a leak is noticed, drying and mold checks may be needed alongside the repair.

What Affects the Cost

Cost varies from job to job, and the plumber confirms the price for your specific job before work begins. The size of the property, how deep or hidden the leak is, which tools are needed, and after-hours timing all play a part. Ask for a written estimate and what it includes before you agree to anything.

Safety First

If water is coming through a ceiling near light fixtures or outlets, stay away from that area and shut off power to it at the breaker if you can do so safely. If water is flowing and you cannot stop it, close the main shut-off valve. If you smell gas, leave the building and call 911 and your gas utility from outside before anything else.

What Happens When You Call

Call now and give your ZIP code when prompted, then stay on the line — it may ring for a moment and the call may be recorded. When someone answers, describe the problem, get a written price and a time window, and book it; nothing is scheduled until you agree. See the full process and how plumbers get into the network →

Who This Is For — and Who It Isn't

A good fit: homeowners and landlords with a rising water bill, a moving water meter, damp spots, or low pressure and no visible source.

Not the right fit: a visible dripping faucet or toilet that a simple repair would fix, leaks on the public side of the water meter that belong to the water utility, or large commercial buildings that need a dedicated commercial contractor.

Frequently Asked Questions — Leak Detection

How do I know if I have a hidden water leak?

The most common signs are a water bill that jumps without a change in use, the sound of running water when everything is off, damp or discolored walls and ceilings, musty smells, warm spots on the floor, and low water pressure. A water meter that keeps moving with all fixtures off is a strong clue.

How does leak detection work?

A plumber narrows down the leak with a mix of tools: a pressure test to confirm a leak exists, acoustic listening equipment to hear it, thermal imaging and moisture meters to see where water travels, and sometimes a camera or tracer gas. The goal is to pinpoint the spot before any opening is made.

How much does leak detection cost?

Cost varies from job to job, and the plumber confirms the price for your specific job before work begins. The main factors are the size of the property, whether the leak is inside walls, under a slab, or underground, which tools are needed, and whether the visit is after hours. Ask for a written estimate first.

Does homeowners insurance cover leak detection?

Coverage varies by policy and by cause, so check with your insurance company before the visit. Many policies treat a sudden leak differently from slow seepage or wear. Ask the plumber for a written report that describes what was found and where, because insurers often ask for documentation.

What is a slab leak?

A slab leak is a water leak in a pipe that runs under or inside a concrete foundation slab. It is hard to see, so signs often show up as warm floor spots, a constantly running meter, or damp flooring. A plumber uses listening and thermal tools to locate it before deciding on a repair.

Can a plumber find a leak without breaking walls?

Often yes. Acoustic listening devices, thermal cameras, and moisture meters let a plumber pinpoint most leaks from the surface, so only a small opening is needed for the repair. Some hidden leaks still require a test hole, but locating the exact spot first keeps the opening as small as possible.

How long does leak detection take?

A simple leak search often takes one to a few hours, depending on the size of the home and how many areas must be tested. Leaks under a slab, behind finished walls, or in long underground lines can take longer. The plumber can give you a realistic time window when you book the visit.

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