Non-invasive leak detection using acoustic listening gear, thermal imaging, and line pressure testing to pinpoint hidden supply, slab, and drain leaks before we open a single wall. You get the exact location and a repair quote, not a guess.
Leak Detection is one part of our plumbing repair coverage in New Hampshire. For the full picture — symptoms, costs, and when to repair vs. replace — start with the complete Plumbing Repair guide, or browse every plumbing repair service we offer.
A hidden leak can waste thousands of gallons and hundreds of dollars before it ever shows a stain, and by the time it does the damage is already done. Leak detection is the diagnostic step that finds water escaping inside a wall, under a slab, or below the yard — precisely — so the repair opens one small area instead of chasing the leak through half the house. We combine acoustic listening equipment, thermal imaging, moisture metering, and system pressure testing to locate the source without guesswork or demolition.
The tools each read a different signature. Acoustic sensors amplify the hiss of pressurized water escaping a pinhole, which we trace to the loudest point over a slab or wall. Thermal cameras see the temperature difference a hot-water slab leak leaves on the floor. A pressure test isolates supply from drain — if the system holds pressure with the water off, the leak is on the drain side; if it bleeds down, it's a supply line. Putting the three together turns a mystery water bill into a marked spot on the floor.
Not every leak announces itself with a puddle. A spinning water meter with every fixture off, a warm patch on a {city} floor, a musty smell with no visible source, or a foundation crack that stays damp all point to water escaping where you can't see it. We locate it, mark it, photograph the reading, and hand you a repair quote for exactly that section — and if the leak turns out to be a simple fixture or a running toilet, we'll tell you that too before anyone opens a wall across {county}.
Signs you need leak detection
Water bill jumped with no change in use
A bill that climbs while your habits stay the same is water escaping somewhere unseen. A leak-detection visit finds where before the waste compounds another month.
New faucet, sink, toilet, or shower fixture set right and sealed.
A faint hiss or trickle in the walls when no tap is open is pressurized water escaping a hidden line. We trace the sound acoustically to its exact source.
Warm spot on the floor
A patch of the United States floor that's warm underfoot usually means a hot-water line is leaking under the slab. Thermal imaging confirms it without breaking concrete to look.
Musty smell or unexplained mildew
A persistent damp or moldy odor with no visible leak means water is feeding mildew inside a wall or cabinet. Moisture metering finds the wet cavity.
Meter dial spins with no water running
Shut every fixture, watch the meter — if it still creeps, you have a leak on the pressurized side. It's the simplest confirmation that a hidden leak exists, and our cue to locate it across your area.
Common causes & what we fix
Slab leaks
Supply lines run under the concrete slab in many the United States homes, and a pinhole there leaks straight into the foundation. Acoustic and thermal locating pinpoints it so only a small area is opened.
Pinhole leaks inside walls
Copper pitted by aggressive water weeps behind drywall long before it stains. Catching it at the detection stage keeps the repair small.
Underground supply-line failures
The buried line from the meter to the house corrodes or gets crushed by roots and settling, leaking into the yard. We trace it above ground before digging.
Failed fittings and connections
Solder joints, compression fittings, and valve bodies weep at the connection first. Pinpointing the exact fitting avoids opening a whole wall run around the United States.
Drain and sewer leaks
Not every hidden leak is pressurized — a cracked drain line leaks only when a fixture runs. Isolating supply from drain by pressure test tells us which system to chase.
Our process
1
Call or schedule online. Book your leak detection in New Hampshire online or by phone and pick a 2-hour window. We confirm in under five minutes with the assigned tech's name and photo.
2
On-site diagnosis. On arrival we diagnose the leak detection on-site — free for most repairs, $39 on minor service calls (waived if you proceed). You see the issue and the fix before we start.
3
Flat-rate quote. You get a flat-rate leak detection quote in writing, good for 30 days — no hourly creep and no add-ons after the fact.
4
Same-visit fix. Most leak detection work finishes the same visit: our trucks carry the common valves, fittings, water heater parts, and fixtures, so a second trip is rare.
How much does leak detection cost in New Hampshire?
Leak Detection the United States starts at from $99, every leak detection quote is flat-rate and presented in writing before work begins — no surprise add-ons, no hourly creep. Seniors (65+) and military save 10% on labor, and financing covers projects over $1,500 at 0% APR for 12 months, with no prepayment penalty.
Why homeowners in New Hampshire choose us for leak detection
We've been a trusted choice since 1974 — over 50 years of family-owned plumbing service across New Hampshire. Our techs are CSLB-licensed (#1098234), background-checked, and complete an internal 12-week training program before rolling on calls alone.
Our leak detection carries a 10-year workmanship guarantee — separate from any manufacturer warranty on the parts themselves. If the leak detection we performed fails because of how we did it, we come back and fix it free for a full decade. Water heaters and fixtures we install are backed by their full manufacturer warranty, and the parts and accessories we fit carry standard 1–5 year warranties by item.
We quote leak detection on honest scope: no unnecessary up-sell, salaried (never commissioned) technicians, and a transparent diagnostic so you see exactly what we see — including the parts still in good shape. If a repair is the right call we say so; if replacement is the better long-term economics, we say that. The flat-rate leak detection quote is written and good for 30 days.
Areas we serve for leak detection
We provide leak detection throughout New Hampshire, with fast coverage in every major New Hampshire metro.
Reach times for leak detection vary by traffic and time of day, so we quote an accurate ETA when you call — and the dispatch line routes straight to an on-call technician, no voicemail in between.
Frequently asked about leak detection
Top questions homeowners searching for Leak Detection near me ask us:
How do you find a leak without tearing up my house?
We use acoustic listening gear to hear the leak, thermal imaging to see temperature differences, moisture meters to map wet areas, and a pressure test to isolate the failing line. That narrows the source to a small marked spot before anything is opened.
Can you find a slab leak under concrete?
Yes — slab leaks are one of the most common calls. Acoustic sensors pick up the leak through the concrete and a thermal camera confirms a hot-line leak, so we open one small section of the United States slab instead of the whole floor.
How much does leak detection cost in the United States?
Detection starts at a flat diagnostic fee and is credited toward the repair when we do the work. You get the exact location and a written repair quote for that section across the United States, with no obligation to proceed.
Why is my water bill high with no visible leak?
The usual hidden culprits are a running toilet, an underground supply line, or a slab leak — all of which waste water without a puddle. A detection visit checks each and tells you exactly which one, serving ZIPs .
How long does leak detection take?
Most detection visits run 1–2 hours depending on home size and how buried the leak is. We locate and mark the source, then walk you through the reading and the repair options before leaving your your area home.