Slab Leak Repair
A slab leak is a pressurized supply line failing inside or beneath your concrete foundation, and it almost never announces itself politely. The usual tells are a hot patch underfoot, a water bill that climbs for no reason, or the hiss of water moving while every tap is closed. The repair that holds up is rarely a patch. On the aged copper that fails this way, we abandon the bad run and route new PEX overhead, so the leak stops and your floor stays whole.
- 60-minute response
- Overhead PEX reroute on aged copper
- Floors and tile left intact
- CSLB License #920054
Heads up: We’re slab and water-line specialists. We don’t service pool/spa leaks, irrigation lines, or natural-gas lines. Anything inside the slab, under the foundation, or in the wall feeding a fixture, that’s exactly what we do.
What is slab leak repair?
Slab leak repair is the work of locating and stopping a water supply line that has failed inside or beneath a home’s concrete slab foundation. Done correctly, it does not mean jackhammering the floor: the failed pipe is isolated and a new line is rerouted overhead through the walls and attic, so the leak is stopped without cutting open the slab. The first half of the job is detection, finding which line failed and where, because the repair plan depends entirely on what the diagnostic confirms.
No Callout Charge
Your service call is free. No trip charges, no surprise add-ons before we’ve looked at anything.
Always On Call
Nights, weekends, holidays, slab leaks don’t wait. We isolate the line, cap the water, and stop the damage now.
Written Estimates
Reroute scope, in writing, with the diagnostic behind it. You see the price before any drywall opens.
Six ways a slab leak job actually plays out
Most of these are the same underlying job arriving in a different shape. The common thread: the foundation itself stays sealed. Which of these your home lands on is what the diagnostic decides, and it’s what shapes the written quote.
Slab Leak Detection
Non-invasive locating: acoustic listening, pressure testing, and a thermal pass to confirm which line gave way, all before any concrete is disturbed.
- Hot versus cold side isolated first
- Acoustic confirmation through the pipe itself
- Thermal scan used to back up a hot-side find
Overhead PEX Reroute
Our default answer to any leak buried in the slab. We retire the failed run and carry a fresh PEX line through the attic instead. No tile lifted, no concrete sawn, no shock to neighboring pipe.
- Two small drywall access points
- New PEX-A routed overhead
- Pressure-tested before we close up
Accessible Spot Repair
When the failure sits at a reachable shutoff, a water-heater connection, or a wall feeding a fixture rather than under the slab, we fix it in place on the same visit.
- Section swapped right at the failure
- Copper or PEX, your call
- Verified under pressure before we leave
Hot-Side Diagnosis
Hot lines wear out ahead of cold ones, so most slab leaks surface there. Pinning the side early keeps us from chasing the wrong run.
- Heater inlet closed to split hot from cold
- Acoustic confirmation on the hot run
- Thermal scan only when it adds certainty
Whole-House PEX Repipe
When several runs are failing on tired copper, or pressure keeps driving repeat leaks, a full repipe is the durable fix. Run overhead, the slab left untouched.
- Hot and cold lines replaced in PEX-A
- Usually staged across a few days
- Pressure regulator checked as part of it
Insurance Claim Assistance
A slab leak with water damage is among the most documentable claims a homeowner can file. We assemble the evidence the adjuster expects and submit it for you.
- Sudden and accidental cause-of-loss
- Reroute justification adjusters can follow
- Direct billing where the carrier allows
How a slab leak gets found without breaking the slab.
Homeowners brace for a plumber to arrive with a jackhammer and a hunch. That is the opposite of how this works. Finding a slab leak is a process of elimination before it is ever a search: each step is a yes-or-no test that cuts the possible fault area roughly in half, so by the time anyone listens for the leak itself, the question has already shrunk from somewhere in the house to this line, this side, about here. We are confirming a hypothesis, not hunting blind, and that is the whole reason it can be done without opening the floor.
The order is fixed on purpose, cheapest and least invasive test first, because each one rules out an entire category of problem before the next begins. Run the steps out of order and you end up guessing with expensive tools and a saw. Run them in order and, by the time anything gets opened, we already know the failed line and roughly its position. That is the difference between one deliberate access cut and a wrecked kitchen floor.
Read the meter first
Before a tool comes off the truck, we watch the water meter with every fixture shut. It answers a single question with no instruments and no assumptions: is this closed system holding water or losing it? A still meter means it holds, and a leak is ruled out before we touch a wall. A creeping one proves water is escaping somewhere, and only then is there a leak worth hunting.
In the slab, or upstream of it?
We shut the main valve at the house. The main is the boundary between two completely different jobs, so settling which side the loss is on keeps us from diagnosing the wrong system. If the meter goes still, the loss is inside the home, in or under the slab. If it keeps turning, the trouble is in the service line between meter and house, a different repair with a different price tag.
Split the hot side from the cold
At the water heater we close the cold inlet. Starting here is playing the odds, not guessing: hot lines fail first, because heat speeds the copper’s corrosion and the constant expand-and-contract of hot water works the pipe against the concrete. If the leak signal eases, it is a hot-side slab leak; if it holds steady, it is cold. A warm floor is a hint, not proof, because hot lines don’t always warm the surface above them, so we trust the acoustic read over the bare foot.
Listen through the pipe, not the floor
This is a method choice, not a preference. Concrete is dense, so it deadens and scatters a leak’s sound, and listening at the surface gives a smeared reading that points everywhere and nowhere. The pipe itself is a continuous metal path that carries the leak’s hiss cleanly to any point we can reach, a shutoff, the heater, a hose bib, and because the sound travels along the metal it also tells us which line is carrying it. We read the material that conducts the signal, never the one that muffles it.
Confirm it under pressure
Acoustics can be fooled, by background noise, by more than one suspect on the line, so we never open anything on a single signal. We cap a gauge onto a hose bib, close the main, and watch the needle. A steady fall is a separate physics that proves the system is actively losing water no matter what we heard, and the speed of the drop estimates how fast. Two independent signals agreeing is what lets us cut one spot with confidence instead of exploring.
Add a thermal pass when it earns its place
Thermal reads surface temperature, which is only a proxy: it works on a hot-side leak under conductive flooring and is easily thrown off by sun, appliances, or a radiant heat path. Treat it as the primary locate and it will send you digging the wrong line, so we keep it as a tiebreaker that confirms the acoustic read, never the thing a cut is based on. Most slab leaks are solved before the camera comes out.
Why we route around a slab leak instead of cutting into it.
On a leak buried in the concrete, the failed run gets bypassed overhead through the attic rather than patched in place. The reasoning starts with what a slab leak actually is: a pinhole in buried copper is rarely a one-off accident, it is the first visible symptom of a process that has been working on the whole run at once.
Buried supply copper fails two ways, and neither is local to the pinhole. From the inside out it pits and erodes, driven by the water’s chemistry, its velocity, and the steady push of high static pressure. From the outside in it abrades where it rubs against the concrete as hot water expands and contracts it. The rest of that line shares the same age, the same water, and the same pressure history, so a second failure is not a risk we invent to sell a bigger job, it is the same process reaching the next weak point. That is why a patch is usually the first repair of several: it treats the symptom and leaves the cause buried and pressurized, where the next leak is again invisible until the damage is done.
A fresh line carried above the slab
New PEX goes up the wall, across the ceiling joists, and back down to the fixture. The failed pipe stays capped in the concrete where it sits. Nothing gets sawn, nothing vibrates loose, and because the new line runs in the open, any future issue shows itself the day it starts instead of hiding under the slab for weeks.
Sawing the slab to patch one spot
Cutting into the foundation to mend one length of worn copper leaves the rest of that line exactly where it was, still buried, still aging on the same clock. The next failure usually lands on the same run, and the saw and hammer drill send vibration through pipe that is already corrosion-weakened elsewhere, so the repair can set off the very leak it was meant to prevent.
Bypass the failing line overhead
For any pipe failure under the concrete, hot or coldA reroute walks new PEX-A through the walls and attic and abandons the bad copper in the slab. The leak stops because that pipe stops carrying water. The case for it isn’t about looks, it’s structural:
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The rest of the run is covered The pinhole that surfaced is a sample of the whole line’s condition, not an isolated event, so a reroute retires the entire vulnerable run instead of one hole in it and waiting on the next.
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No demolition near weakened pipe Saws and hammer drills send vibration through copper that is already thinning elsewhere on the run. A patch can solve the leak you see and start one you can’t. A reroute sidesteps that risk entirely.
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It turns a hidden line into a visible one The abandoned run stops being an unmonitorable pipe in the concrete; the new line is overhead and in reach, so the next surprise, if there ever is one, is one you can actually see coming.
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Nothing pulled up The work runs through two small drywall openings: no flooring torn out, no slab to re-pour, no finish carpentry to redo afterward.
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Stands behind a warranty New PEX carries a parts-and-workmanship warranty. A patch on tired copper does not, and no honest plumber will pretend otherwise.
Accessible spot repair
When the leak is NOT in the slabWe only steer toward a spot repair when the leak isn’t actually trapped in the concrete. It sits somewhere we can reach without opening the slab, and the diagnostic almost always tells us that up front.
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At a reachable shutoff or angle stop Under a sink, behind a toilet, at the laundry box. We swap the failing fitting and we’re done.
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At the water-heater connection A flex line, a dielectric union, or the inlet itself, all visible and all fixable without opening anything.
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Inside a reachable wall cavity A pinhole behind drywall feeding a fixture, not under the slab. A small cut, a section swap, a patch.
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Never through the slab If the diagnostic puts the leak in the concrete, the concrete stays closed and we reroute. No exceptions, whatever the price looks like.
If a plumber wants to saw your slab open to patch one spot on aged copper, ask what makes the rest of that run different from the piece that just failed. Usually nothing does, same age, same water, same pressure, and that is the whole answer.
Our thanks to the people who keep our communities running..
A 5% discount (up to $200 off) for first responders, military, healthcare workers, teachers, seniors, and nonprofit staff in the communities we serve. Mention "Community Heroes" when you call; we’ll take care of the rest.
Applies to repairs over $500. Cannot be combined with other promotions. Proof of eligibility may be requested at the time of service.
Slab leak repair in your city
We dispatch from offices across Southern California. Pick your city for local response times, neighborhoods, and the team that serves you.
Cities served by our Murrieta office
Cities served by our Aliso Viejo office
Cities served by our Irvine office
Cities served by our San Diego office
Slab leak specialists since 2008.
Cali's Choice
Leak detection and slab leak specialists, family-run and serving Southern California homeowners.
Slab leaks located and repaired
Spot repairs and overhead reroutes, across thousands of service calls combined.
California License
C-36 Plumbing classification. Bonded and insured statewide.
Leak detection
Free when we do the slab repair.
What homeowners say about our slab work.
Real reviews posted to our Google Business Profile.
I suffered a slab leak and then an unrelated leak. Sergio was the lead, very upfront, courteous, and did very good work with real attention to detail. That experience was great, so I called again for the next problem and it was the same. I would recommend Sergio and Cali's Choice to anyone.
A water leak under our slab was carefully fixed by Sergio and Levi. They worked for hours straight so that we could have running water that evening. Estimates were reasonable, repairs were explained, and the areas were cleaned up at completion. What more can one ask for?
Awesome service. We had a slab leak. The leak was detected and the repair scheduled right away. The team was respectful, left things clean, and the work was fairly priced. I will be calling them for all plumbing repairs in the future.
A slab claim usually turns on the reroute. We document it so it holds.
With a slab leak, the water damage is rarely the argument: carriers tend to grant that part. The money is decided on the pipe repair, specifically whether the adjuster accepts a reroute or insists on a cheaper patch through the slab. A default-minded carrier prices the patch and balks at rerouting aged copper, and that is exactly where a homeowner loses ground if the file only lists a loss instead of making the engineering case.
So we build the claim around that argument at the diagnostic, then carry it to the adjuster ourselves, so the reroute is justified on the record before it is ever questioned, not defended after it has already been denied.
- The loss, written as sudden and accidental. Coverage hinges on that finding, so the file leads with how the line gave way, which side it was on, the build year, and the copper it was run in: the line between a covered event and a wear-and-tear denial.
- The diagnostic, not just the damage. The locating read, the access point, and the failed copper are photographed and logged, because the reroute case rests on showing why that line failed, not merely that water turned up.
- The repair argued, not just listed. The scope sets spot repair against reroute with the reasoning attached, so an adjuster pricing a patch can see why the reroute is the repair that actually holds on aged copper.
- The reroute defended up front. Carriers often wave a slab patch through and push back on a reroute, so the engineering rationale goes on the record early, before the correct repair can be downgraded to the cheap one at review.
- We talk to the adjuster, you don’t. Pipe-failure questions and evidence requests come to us, so you are not stuck translating between a carrier and a plumber in the middle of your own claim.
What slab leak repair actually costs.
The honest answer is that no website can hand you an exact figure. The same diagnosis can land on very different jobs depending on what we find: one line or two, single story or two, an open attic or a finished one. What we can do is lay out exactly what moves a slab repair up or down, so the written quote reads as logic rather than a number pulled from the air.
What moves a slab job up or down
How much line gets rerouted
A single hot run from the heater out to one wing of the house is the common case. Multi-line reroutes and full repipes scale the work up from there.
Pipe material and age
Older Type-M copper that has failed once tends to mean the rest of that run is close behind, which can move the recommendation from a one-line reroute toward a full repipe.
Run length and attic access
How far the new line travels and how workable the attic is both feed the labor. A single-story home with an open attic is quick; a two-story with a finished one takes longer.
Number of access openings
Most reroutes need two small drywall cuts. A more involved run can call for a third. Patching and texture-matching is written into the quote, not added after.
Water damage already done
If the leak has soaked drywall or flooring, drying and rebuild is a separate scope handled by a sister company. We document it for your claim and keep it off our repair number.
What is a slab leak?
A slab leak is a leak in one of the pressurized water lines that run inside or beneath a home’s concrete foundation. Because the pipe sits in concrete, the water often has nowhere to show itself, so the first signs are indirect: a warm spot on the floor, a climbing water bill, or the sound of water running with everything shut off.
What are the warning signs of a slab leak?
The four most common are a warm patch on the floor in one specific spot, which points to a hot-side leak, a water bill that jumps with no change in usage, the sound of running water when every fixture is off, and a water meter that keeps creeping after you’ve shut everything down. Any one of those is worth a call before the damage spreads.
How do you find a slab leak without breaking the concrete?
We start at the meter to confirm water is escaping, then isolate the hot side from the cold at the water heater. From there we listen acoustically through the plumbing itself, at shutoffs, the heater, and reachable runs, not through the slab, which only muffles the sound. A pressure test confirms the leak is active, and on a hot-side leak a thermal scan can add a second opinion. Nothing gets opened until the failed line is confirmed.
Do you have to break the floor to repair a slab leak?
No. When a line under the slab has failed, we route new PEX overhead through the attic and leave the old copper capped in the concrete. That means two small drywall openings instead of a jackhammer in your living room, and no demolition vibration that could disturb the rest of the run.
Why reroute the line instead of patching the leak?
Because a patch fixes one spot on a run that is usually failing along its whole length. When one stretch of aged in-slab copper gives way, the next is statistically close behind, so patching tends to be the first of several repairs. Cutting the slab to reach it can also jar nearby pipe into leaking. A reroute replaces the whole vulnerable line and carries a warranty a slab patch can’t.
What is the difference between a spot repair and a reroute?
A spot repair only happens when the leak isn’t actually in the slab: it’s at an exposed shutoff, a water-heater connection, or an accessible wall cavity, and we fix it in place. For any leak buried in the concrete the answer is a reroute, because patching one section often sets up the next failure and the demolition itself can disturb adjacent pipe.
Is it safe to repair a slab leak on a post-tension foundation?
Yes, as long as nobody cuts the slab. Post-tension foundations carry tensioned steel cables and should never be sawn into. That’s exactly why an overhead reroute is the right call: it bypasses the failed line entirely without touching the foundation. We treat conventional slabs the same way, so the approach doesn’t change.
Will my insurance cover a slab leak?
Most HO-3 policies cover the sudden-and-accidental water damage a slab leak causes, the wet drywall, flooring, and dry-out, while the pipe repair itself is typically on the homeowner. We document both sides so the adjuster has what they need, and we handle the claim paperwork end to end.
How long does slab leak repair take?
Detection is usually the same visit, often within a couple of hours. A single-line overhead reroute is commonly a one-day job. A whole-house repipe is larger and tends to run across a few days, staged so the home keeps water. We give you the timeline in writing with the quote, before anything starts.
Do you repair pool, irrigation, or gas line leaks?
No. We’re slab and water-line specialists, so pool and spa leaks, irrigation lines, and natural-gas lines are outside what we do. Anything inside the slab, under the foundation, or in a wall feeding a fixture is squarely our work, and we’ll point you to the right trade for the rest.
Think you have a slab leak? We find it before we fix it.
A specialist, a written quote, and a clear spot-repair-versus-reroute recommendation before we touch a thing. If we can’t help, we’ll tell you who can.
Cali's Choice Leak Detection & Emergency Plumbing · CSLB #920054