# Slab Leak Rerouting in Dallas

> Slab leak rerouting in Dallas: we abandon the leaking supply line under the slab and run new pipe through the attic and walls, inspected. Get an estimate.

URL: https://fullboredallasrepiping.com/slab-leak-rerouting/

When a hot or cold supply line leaks under your slab, we abandon that line and run new pipe overhead through the attic and down interior walls instead of breaking the concrete.

Call (469) 846-9377

Last Updated: November 10, 2026

Floors stay intact

We run the new line through the attic, so the slab and the flooring on it are left alone

Supply lines only

Rerouting covers pressurized hot and cold water lines; drain and sewer leaks are a separate job

There is a warm spot on the kitchen tile. The water bill jumped and nothing is running. The leak detection company has marked an X on the floor and said “supply line under the slab.” Now you are choosing between breaking concrete and going around it. For slab leak rerouting, Dallas houses usually get a new line run through the attic and down an interior wall, and the leaking one is left capped in the concrete. [Fullbore Dallas Repiping](https://fullboredallasrepiping.com/) replaces water supply lines in Dallas homes, from a single bathroom branch to the whole house.

Your floors stay whole, and the line that failed is replaced end to end instead of patched at one spot. This is supply-side work only: it covers the pressurized water lines, not drains or the sewer, and it does not repair a foundation.

> What this service does not cover
>
> A leaking drain or sewer pipe under the slab works by gravity and cannot be moved into the attic, so it needs a drain and sewer specialist. Settlement, cracks or slab movement need a foundation professional. We handle the water supply side of the problem only.

## What we check on the first visit

We make sure the leak is on a supply line, and which one, before we price a reroute. With every fixture off, a turning leak indicator on the water meter means something under pressure is leaking; a drain leak does not move the meter. A warm floor, a water heater that runs more than it should, or the sound of running water near a wall points to the hot side. If you have leak detection findings, from acoustic listening or from isolating and pressure testing each line, bring them; they narrow the source to one run.

Then we map that run. In many slab-on-grade houses, supply lines leave a trunk under the concrete and rise inside a wall at each fixture, so we trace where the failed line starts and which fixtures it feeds. We also go into the attic to find a clear path, check headroom and pick where to drop down each wall.

## Why lines under a Dallas slab fail

Many Dallas houses were plumbed with copper, or galvanized steel in older homes, laid under or in the slab before the concrete was poured. Nobody can see that pipe, and it wears in ways an exposed line does not. Copper can rub thin where it touches concrete, rebar or gravel as the slab moves and the pipe grows with each hot-water draw. Hot lines go through the most of those cycles, which is one reason a warm floor is such a common first sign.

A second leak on the same under-slab line is a strong hint that the rest of that pipe is in similar shape, which is the case for replacing the run rather than one more patch. No single cause explains every pinhole; our [guide to recurring pinhole leaks](https://fullboredallasrepiping.com/guide/recurring-pinhole-leaks/) explains why the pattern matters more than any one theory.

## Why go around the slab?

Opening a slab means lifting flooring, breaking concrete over the leak, repairing one spot on a pipe that is the same age everywhere, then pouring and refinishing. Rerouting skips the concrete entirely and replaces the full length of the failed line. The trade-off is a new path through the attic and a few openings in drywall, which is usually easier to put back than tile or wood floors.

Post-tensioned slabs add a firm limit. Many newer Dallas-area slabs are post-tensioned, with steel tendons stressed after the pour, and cutting one is dangerous and can damage the structure. Nobody should cut a post-tensioned slab without the structural information: the drawings, the stamp near the garage or an engineer’s direction. Where that information is missing, going overhead is the safer default.

Has leak detection already found the line?

Send us the findings and the fixtures on that line, and we will price rerouting it through the attic.

Call (469) 846-9377

## How we run the new line

We usually run the new line in PEX, with copper as the other option; see [PEX repiping](https://fullboredallasrepiping.com/pex-repiping/) and [copper repiping](https://fullboredallasrepiping.com/copper-repiping/) for the trade-offs. From a tee at the water heater or the trunk, it climbs into the attic, runs across the joists and drops down an interior wall to each fixture. Summer attic heat sits within the rating of listed PEX, but sunlight breaks it down, so we keep the tubing out of UV light, support it at its maker’s spacing and keep it clear of flues.

Freeze protection matters just as much. The prolonged February 2021 winter storm, documented by the National Weather Service, showed how cold a Dallas attic can get. We insulate the line and run it low, against the ceiling drywall and under the attic insulation, so it stays closer to the heated house. The [attic pipe routing and freeze protection guide](https://fullboredallasrepiping.com/guide/attic-pipe-routing-and-freeze-protection/) covers both concerns. We cut and cap the old line where it leaves the slab at each end we can reach, and record the reroute so a later plumber knows the slab line is dead.

## Will you have to open walls?

A few small openings, yes: at the top plate where each line drops from the attic, and at each fixture where it connects. Those are usually small cuts in drywall, but a fixture behind tile or a cabinet back can widen the job. Your estimate lists each opening and says who patches, textures and paints it. The [wall openings and drywall repair guide](https://fullboredallasrepiping.com/guide/wall-openings-and-drywall-repair/) covers what a patch scope should include.

The work needs a permit. Rearranging supply piping falls outside the City of Dallas leak-stop exemption, and the 2021 International Plumbing Code with Dallas amendments applies. We submit the permit through DallasNow, and the City inspects the rough-in with the walls open; covering new pipe first can bring the City’s $200 unauthorized concealment fee. The [Dallas repiping permit guide](https://fullboredallasrepiping.com/guide/repiping-permits-dallas/) covers the steps.

## How we price a reroute

We price each reroute after the first visit, from the line and the house. The main pieces are the length of the new route from source to fixture, how many fixtures the abandoned line served, whether it is hot, cold or both, and how much attic room there is to work in. A two-story house, a low-slope roof or a fixture far from any interior wall all add work.

Fixture walls behind tile or cabinets, the permit and inspections, and the drywall, texture and paint scope also move the number, and your written estimate lists each. The [repiping cost estimator](https://fullboredallasrepiping.com/tools/repiping-cost-estimator/) shows how each driver adds up, and the [Dallas repiping cost guide](https://fullboredallasrepiping.com/guide/repiping-cost-dallas/) explains why a reroute and a slab repair are priced so differently.

## Before you decide

When one under-slab line has already failed, our [repair-or-repipe guide](https://fullboredallasrepiping.com/guide/repair-or-repipe/) helps you decide whether to reroute one line or all of them; the broader option is [whole-house repiping](https://fullboredallasrepiping.com/whole-house-repiping/). For what a reroute is like to live through, read the [guide to the repiping process and timeline](https://fullboredallasrepiping.com/guide/repiping-process-and-timeline/). If the meter shows no leak but the floor is wet, the source is probably not a supply line, and neither a reroute nor [partial repiping](https://fullboredallasrepiping.com/partial-repiping/) will help until it is found.

Talk to us about your house

Call (469) 846-9377

Standards this work follows

- 2021 International Plumbing Code with City of Dallas amendments
- ASTM F876/F877 PEX tubing and fittings, or ASTM B88 Type L/M copper
- Manufacturer instructions for attic support, UV protection and insulation
- NSF/ANSI 61 and 372 for drinking-water components
- Structural drawings or engineer input before any cut in a post-tensioned slab
- DallasNow permit with rough and final inspection

## What's included

- A check of the meter test and leak detection findings to confirm which supply line failed before we price a reroute
- Isolation and capping of the abandoned under-slab line at both ends where reachable
- A new hot or cold line routed through the attic and down interior walls to the affected fixtures
- Support, UV protection and pipe insulation for the attic run per the tubing maker's instructions
- Transitions to the retained piping at the fixture and at the source
- Pressure test of the new line before walls close
- Permit, rough and final inspection coordination
- A written list of wall and ceiling openings and who closes them

## Three answers to a confirmed supply leak under the slab

|  | Spot repair through the slab | Reroute the one line | Repipe the house overhead |
| --- | --- | --- | --- |
| What happens to the leaking pipe | A section is exposed and repaired in place | It is cut, capped and left in the slab | Every under-slab supply line is abandoned |
| Access | Floor covering removed and concrete opened over the leak | Attic plus small openings at the top and bottom of interior walls | Attic plus openings at each fixture wall |
| Post-tensioned slab | Not cut without the structural information | Concrete stays intact | Concrete stays intact |
| Other under-slab lines | Stay in service and keep aging | Stay in service and keep aging | None left under the slab |
| Fits when | The leak is located precisely and the slab can be opened safely | One line has failed and the rest of the piping tests sound | Several lines have leaked or the material is near the end of its life |

## Related resources

- Learn [Repiping through attic space in Dallas: how should new lines handle heat and freezes?](https://fullboredallasrepiping.com/guide/attic-pipe-routing-and-freeze-protection/)Getting your water lines out of the slab usually means putting them in the attic. That solves one problem and raises two more, July heat and February cold, and the route, support and insulation have to answer both.
- Decision Guide [Should you repair or repipe a house with leaking pipes?](https://fullboredallasrepiping.com/guide/repair-or-repipe/)One leak is a repair. A pattern of leaks on the same pipe is a decision. Here's how to tell which one your Dallas house has, and what sits between the two.
- Learn [Wall repair after repiping: where do the openings go and who patches them?](https://fullboredallasrepiping.com/guide/wall-openings-and-drywall-repair/)A repipe needs access openings, and your walls close only after the new piping is tested and inspected. Where the holes go, how big they are and who finishes them should all be settled on paper first.
- Learn [Do Dallas repiping permits apply to a repipe, and how do inspections work?](https://fullboredallasrepiping.com/guide/repiping-permits-dallas/)A repipe inside the City of Dallas is permitted plumbing work. Here's how the permit, the rough-in and final inspections and the fees fit around your job.
- Cost Guide [Repiping cost in Dallas: what sets the price of a repipe?](https://fullboredallasrepiping.com/guide/repiping-cost-dallas/)Our typical ranges for a whole-house repipe, why your house can land well above or below the house next door, and how to read two quotes side by side.
- Learn [What causes recurring copper pinhole leaks?](https://fullboredallasrepiping.com/guide/recurring-pinhole-leaks/)A copper pinhole is the end of a slow process inside the pipe wall. When they keep coming, where and when they show up tells you more than any single leak.

## How a Dallas repipe usually runs

1. First visit We count 14 fixture connections, trace the copper from the main shutoff in the garage, find the original lines running under the slab, check static pressure and the PRV, and look in the attic for headroom, insulation depth and a clear path from the garage to both bathrooms.
2. Written estimate Your estimate names PEX-A with expansion fittings, a home-run manifold beside the garage water heater, new quarter-turn stops, the old under-slab copper capped and left in place, the number and location of wall openings, and whether patch, texture and paint are included.
3. Permit Rearranging supply pipe is outside Dallas's limited exemption for stopping a leak, so the repipe is filed as permitted work through DallasNow before any pipe is cut. We keep the permit record with your estimate so you have both for your files.
4. Protection and openings Floors along the work path are covered, furniture is moved back from the wet walls, and small openings are cut behind the toilets, at each shower valve, under the sinks, at the washer box and at the kitchen sink wall.

## What this work looks like

Insulated PEX hot line strapped to attic joists above blown-in insulation, running toward a bathroom wall

Copper supply line cut and capped where it rises from a concrete slab inside an opened vanity wall

Small drywall opening at a kitchen wall top plate where a new PEX line drops from the attic

Pressure gauge on a newly rerouted PEX line beside a shower valve before the wall is closed

Before

After

Leak under the slab confirmed?

Send us the leak detection findings and the fixtures on that line, and we will price a reroute.

Call (469) 846-9377

## Slab leak rerouting questions

### How can a Dallas homeowner tell if a slab leak is on a water supply line?

Turn off every fixture and appliance, then watch the water meter. If the leak indicator keeps turning, something under pressure is leaking. A warm spot on the floor points to a hot line. A drain or sewer leak under the slab does not move the meter, because that pipe is not under pressure. Leak detection then finds which supply line it is.

### Is rerouting better than breaking out the slab to fix the leak?

Often, but not always. A reroute leaves the concrete alone and replaces the whole failing line rather than one spot on it, which matters when the same pipe may leak again further along. A spot repair can make sense when the leak is pinpointed, the slab is conventional and the flooring above is easy to lift. We will tell you which fits.

### Can a plumber cut into a post-tensioned slab in Dallas to reach a leak?

Not without the structural information first. Post-tensioned slabs carry steel tendons under very high tension, and cutting one can injure people and damage the foundation. Some are marked with a stamp or placard near the garage or entry. When a slab may be post-tensioned, the drawings or an engineer settle where it can be opened, which is one reason we usually reroute overhead.

### Does a rerouted line in a Dallas attic need protection from heat and freezing?

Yes. We keep PEX in the attic out of sunlight, support it at the spacing its maker specifies and cover it with pipe insulation. The February 2021 storm showed how cold a Dallas attic can get. Running the line low against the ceiling drywall and under the attic insulation, rather than over it, adds a margin.

### Does slab leak rerouting cover a leaking drain or sewer pipe under the house?

No. Rerouting works for pressurized hot and cold supply lines, which can be abandoned and replaced through the attic. Drain and sewer pipe works by gravity and cannot be moved overhead, so a leak there is a separate repair for a drain and sewer specialist. Foundation repair is also a separate job.

## Related services

Partial repiping

We replace a named part of your hot and cold supply piping and leave the rest in service, with your estimate saying exactly where new pipe meets old and what stays.

Whole-house repiping

We replace every hot and cold supply line from the main shutoff to each fixture, usually rerouted through the attic on slab houses, then tested and inspected before the walls close.

PEX repiping

We repipe with one listed PEX tubing and fitting system, laid out as trunk-and-branch or a home-run manifold and routed to handle Dallas attic heat and winter freezes.