Leak Detection South Bay
Gas and water leak detection for South Bay homes and businesses.
Find the Leak Before It Gets Worse
Knockout Plumbing has been locating and diagnosing gas and water leaks throughout the South Bay for over 20 years. Hidden leaks — inside walls, under slabs, or underground — often go undetected for months, causing structural damage, mold, and dramatically higher water bills before anyone realizes there's a problem.
South Bay homes, particularly those built before 1980, frequently have aging copper, galvanized, and cast iron lines that are prone to corrosion and pinhole leaks. We use non-destructive detection methods to locate the leak accurately before any walls are opened or concrete is touched.
- Gas and water leak detection
- Non-destructive location methods
- Same-day response for suspected gas leaks
- Licensed, bonded & insured
Think you have a leak?
Gas leaks are an emergency — leave the building and call immediately. For suspected water leaks, the sooner we locate it, the less damage there is to repair.
(310) 493-0348Available 24/7 for gas and water leak emergencies
Signs You May Have a Hidden Leak
Many leaks give warning signs long before they become obvious. Don't ignore these.
-
Water Stains or Discoloration
Unexplained stains on ceilings, walls, or floors — especially if they grow over time — often indicate water leaking from a pipe behind or above.
-
Musty or Moldy Smell
A persistent musty smell — particularly in areas that don't get wet — is a common sign of a slow water leak feeding mold growth inside the wall or under the floor.
-
Hissing Sounds
A hissing or whistling sound near a gas appliance, wall, or the meter is a strong indicator of a gas leak. Leave the building immediately and call us and the gas company.
-
Unexplained High Water Bills
A spike in your water bill without a clear reason — no extra use, no new irrigation — often means water is running somewhere it shouldn't be.
-
Soft Spots or Warped Flooring
Flooring that feels spongy, buckling, or is lifting near a wall, toilet, or appliance usually means moisture has been accumulating underneath for some time.
-
Gas Smell / Rotten Egg Odor
Natural gas is odorless, but utility companies add a sulfur compound so leaks are detectable. A rotten egg smell near appliances, outlets, or outdoors is a gas leak emergency — get out and call immediately.
Gas leak? Do not use light switches, open flames, or electronics. Leave the building immediately, then call us and SoCalGas. Do not re-enter until cleared.
What We Detect
We locate leaks across all plumbing and gas systems throughout your home.
Gas Line Leaks
Gas leaks at appliances, flexible connectors, buried supply lines, and interior gas piping. We locate the source precisely so repairs are targeted — not exploratory.
Water Supply Line Leaks
Pinhole leaks and slow seeps in copper, galvanized, and PEX supply lines — often hidden inside walls or below floors. Older South Bay homes with original piping are particularly susceptible.
Slab Leaks
Water lines running under concrete slabs can develop leaks from corrosion, soil movement, or pressure changes. Slab leaks often cause warm spots on floors, cracking, or unexplained water pooling. We locate them without breaking concrete unnecessarily.
Underground Leaks
Buried water or gas lines in yards and driveways can leak for a long time before surfacing. Signs include unexplained wet patches, sinkholes, or abnormally lush grass. We locate underground leaks without unnecessary digging.
Fixture & Supply Stop Leaks
Slow leaks at toilets, supply stops under sinks, and fixture connections are easy to overlook but can cause significant water damage to cabinetry and subflooring over time. We inspect and diagnose these as part of any leak assessment.
Hidden Wall & Ceiling Leaks
Leaking pipes inside wall cavities or above ceilings are often only discovered after visible damage appears. We locate the source before opening walls, reducing unnecessary repair work.
How We Find Your Leak
We locate leaks accurately before any walls are opened or concrete is disturbed.
-
Assess the symptoms
We start with a full walkthrough — checking meter readings, water pressure, visible staining, and any other indicators you've noticed. This narrows down the likely source and type of leak before we use any detection equipment.
-
Locate the leak
Using non-destructive detection methods, we pinpoint the leak's exact location. For water leaks this may include pressure testing, acoustic listening equipment, or thermal methods. For gas leaks we use electronic detection equipment to trace the line.
-
Diagnose the cause
We identify why the leak is occurring — corrosion, a failed fitting, ground movement, or pressure issues. Understanding the cause determines whether a targeted repair is sufficient or whether a larger section of pipe needs attention.
-
Recommend repair options
We give you a clear explanation of what was found, where it is, and what the repair options are — including cost and scope. We don't start work until you've approved it. In many cases we can complete the repair the same day.
Serving the South Bay
We provide gas and water leak detection throughout the South Bay, including:
Frequently Asked Questions
How do I know if I have a hidden leak?
The most reliable indicator is your water meter. Turn off all water-using appliances and fixtures, then check if the meter is still moving. If it is, water is flowing somewhere in the system when it shouldn't be. Other signs include unexplained high bills, water stains, warm spots on the floor, and musty odors.
Is leak detection destructive?
Not in the detection phase. We use non-destructive methods to locate the leak before anything is opened. Once we know exactly where it is, any access needed for the repair is targeted and minimal — not exploratory. This is why accurate detection saves money on the repair itself.
Can you respond to emergency leaks?
Yes. We prioritize suspected gas leaks and active water emergencies. Call us and we'll give you an honest ETA. For gas leaks: leave the building, don't operate any switches, and call us and SoCalGas from outside before we arrive.
Do you repair the leak too, or just locate it?
We do both. After locating and diagnosing the leak, we walk you through the repair options, give you upfront pricing, and can complete most repairs the same day. You're not handed off to a separate company.
Do you detect gas leaks?
Yes. We locate gas leaks in interior lines, appliance connections, flexible connectors, and buried exterior supply lines. Gas leaks are treated as emergencies — if you smell gas, don't wait to call. Get outside first, then call us.