Slab Leak in DFW: Repair, Reroute, or Repipe?
Bradley Earp, Responsible Master Plumber, TSBPE M-43562
A slab leak is a leak in a water line or a drain line under the concrete. The first job is to find which one it is. The second is to choose a fix that matches the pipe, the leak, and the rest of the system: a targeted repair, a PEX reroute around the failed run, or a whole-house repipe.
Every job starts with a $97 diagnostic and a written quote before work begins. We're open Monday through Saturday, 7 AM–7 PM, and closed Sunday.
Water-line leak vs. drain leak
These two problems can feel similar from the living room — a soft spot, a high bill, a smell, a foundation that has started to move — but they are not the same pipe and they are not priced the same way.
A pressurized water-line leak (the hot or cold supply under the slab) often shows up as unexplained water use, a meter that still moves when every fixture is off, a warm spot on the floor, the sound of running water, or a sudden drop in pressure. The line is under pressure, so it can waste a lot of water in a short time and soften the soil under the slab.
A drain-line leak under the slab is not a supply leak. It is wastewater escaping from the drain piping, which in many pre-1980 DFW homes is original cast iron. Clues include drains that clog again a few weeks after they are cleared, sewer odor, slow tubs or showers, drain flies, or damp soil at the edge of the slab. For the neighborhoods and failure modes behind that, see our guide to cast iron sewer pipes in pre-1980 Plano and Richardson homes.
Both kinds of leak can move a slab here. About 74.5% of Collin County's rated soil is high or very high shrink-swell clay (USDA soil survey, summarized by HGS Engineering). Water under the house gives that clay more to work with.
How we confirm it: residential leak detection for a 1–2 bathroom home is $470; drain leaks are confirmed with a camera inspection as needed. We will not ask you to choose a repair path before we know which pipe is leaking. Repair work starts after a written quote.
Option 1: Direct repair
A direct repair makes sense when the problem is localized and the rest of the pipe is still sound.
Drain leaks. If the camera shows one break or one failed section in otherwise serviceable pipe, we can reach it by tunneling from outside so finished floors stay in place. Under-slab drain work is priced at our published sewer rates: $3,375 covers the first 5 feet of tunnel (a 5-foot minimum), then $425 per additional foot, plus $1,150 per access hole. If a yard section is involved, open trenching is $180 per foot. The written quote is those quantities, not a vague range. For how those numbers add up on a drain job, see Sewer Line Replacement Cost in DFW and the sewer line calculator. The written quote, not the calculator, is the price, and it will include the 5-foot minimum.
If the camera shows scale and channeling along the run, a single spot repair is usually a stalling tactic. Full replacement with PVC, still tunneled from outside, is often the better long-term path. We do not line pipes. Where a yard section is still round and the route is open, trenchless pipe bursting can replace that yard run without a full-length trench. Under-slab work is still tunneled.
Water-line leaks. A first, isolated supply leak can sometimes be repaired in place when we can reach it without wrecking finished floors. Whether that is the right call depends on what the locate shows, the age and material of the pipe, and whether this is the first leak or the second. A water-line slab leak spot repair typically runs $2,250–$4,550, confirmed in a written quote after we locate the leak.
Option 2: Reroute in PEX
A reroute leaves the leaking under-slab supply run in place and abandoned, and brings a new PEX line to that fixture or fixture group through the attic or the walls. Repipes and water lines are PEX only. We do not reroute in copper.
We price this work per drop. A drop is one water supply connection to a fixture:
- A full bath counts as 5 drops (toilet, lavatory, and tub or shower).
- A half bath counts as 3 drops (toilet and lavatory).
- Each outdoor hose faucet counts as 1 drop.
- Each additional appliance or fixture — dishwasher, clothes washer, water heater, ice-maker line, and so on — counts as 1 drop.
You can walk the house and write the number down before we arrive. The written quote uses that count and the foundation type (slab homes are usually routed through the attic and down the walls; pier-and-beam work can run under the floor). We do not publish a per-drop dollar rate in this guide. The quote is the price, and 15% off applies if you approve that written quote the same day.
If the leak is not under the slab at all, but between the meter and the house — a soggy yard, a meter that spins with everything off, low pressure throughout — that is a different job: a new PEX service line from the meter to a shutoff you can actually reach. A typical yard water line replacement runs $3,500–$4,500, confirmed in a written quote after we see the run.
Option 3: Whole-house repipe
A whole-house repipe replaces the hot and cold supply piping from the main shutoff to every fixture, in PEX, again priced by counting drops. A water or sewer repipe typically takes about 3–5 days, and sheetrock we open is reinstalled. If you request it after a full water line replacement, we can arrange an interior contractor to paint-match, tape, bed and texture for $200 per patch.
This is the better path when a second leak has already shown up, when pinholes or rusty water are widespread, or when the original material (galvanized, aging copper, or polybutylene) is failing in more than one place. Fixing one leak and leaving the rest of a failing system in the slab is how houses end up with a second emergency six months later.
How we count drops, why slab and pier-and-beam routes differ, and how the yard line is priced separately are in Whole-House Repipe Cost in DFW. City pages for the work itself are Plano, Richardson, and Garland.
How to choose: first leak vs. second leak, pipe age, and flooring
Use this as a starting point, not as a substitute for the diagnostic. Your written quote will say which path we recommend and why.
| What you have | Typical path | What we need to see first | How it is priced |
|---|---|---|---|
| First isolated supply leak, rest of the line looks sound | Direct repair if we can reach it, or a PEX reroute to that fixture group | Leak locate and a walk-through | Water-line spot repair is typically $2,250–$4,550, confirmed in the written quote. Reroutes are quoted per drop. |
| Second supply leak, multiple pinholes, rusty water, or old galvanized / polybutylene | Whole-house PEX repipe, or a larger reroute | Walk-through and a full drop count | Quoted per drop. See the repipe guide. |
| Drain leak in otherwise sound pipe | Spot repair by tunneling | Camera inspection | $3,375 covers the first 5 ft of tunnel, then $425/ft, plus $1,150 per access hole, itemized. |
| Drain leak in scaled or channeled cast iron | Replace the under-slab drains with PVC, tunneled from outside | Camera inspection | Same published sewer rates, usually more tunnel footage. |
| Finished tile or hardwood you do not want opened | Prefer tunneling (drains) or an attic/wall PEX reroute (supply) rather than opening the slab | Locate or camera, plus a look at the route | Same rate basis as above; floors stay in place when we tunnel or reroute from outside. |
| Leak in the yard, meter to house | New PEX yard line, not a house repipe | See the run | $3,500–$4,500 typical, confirmed in the written quote. |
If the leak is on the drain line toward the street, ownership can matter. In Plano, Richardson, and Garland, the homeowner owns the sewer line from the house out to the City connection or cleanout. Details are in the sewer cost guide; when in doubt, we will tell you what the camera showed and who to call.
Insurance and next steps
This is general information, not legal advice, and not a promise about any policy. Many Texas homeowners policies treat sudden water damage, and sometimes the cost to access a leak, differently from the failed pipe itself. Sewer lines are often a separate question. Read your policy and ask your agent. Our sewer line replacement cost guide has a short version of the same point.
Every quote still starts with the $97 diagnostic. Approve the written quote the same day and the price is 15% off. Financing is available, subject to credit approval. If you already have a written, itemized estimate from another licensed plumber for the same scope, our Certified Price Review applies: we'll match or beat apples-to-apples plumbing scopes (terms apply; it does not obligate us to match).
FAQs
Should I repair a slab leak, reroute it, or repipe the house?
It depends on whether the leak is a water line or a drain, whether this is the first failure or the second, and what condition the rest of the pipe is in. A first, isolated supply leak may be a candidate for a direct repair or a PEX reroute. Repeated leaks or failing original pipe usually point to a whole-house PEX repipe. Drain leaks are confirmed with a camera and repaired or replaced at our published tunneling rates. The $97 diagnostic and the written quote are how we pick a path for your house.
How can I tell if my slab leak is a water line or a drain line?
A supply leak often shows up as a spinning meter, a warm floor, or a high water bill. A drain leak often shows up as repeat clogs, sewer odor, or slow fixtures. Those are clues, not a diagnosis. We confirm supply leaks with leak detection and drain leaks with a camera as needed.
How much does it cost to fix a slab leak in DFW?
Every job starts with a $97 diagnostic and a written quote. Residential leak detection for a 1–2 bathroom home is $470. A water-line slab leak spot repair typically runs $2,250–$4,550. Under-slab drain repairs and replacements start at $3,375 for the first 5 feet of tunnel, then $425 per additional foot, plus $1,150 per access hole ($180 per foot if we trench in the yard). A typical yard water line from the meter to the house is $3,500–$4,500. Supply-line reroutes and repipes are quoted per drop after we count your fixtures; we do not publish a per-drop dollar rate in this guide. 15% off applies when you approve the written quote the same day.
Do you reroute in copper?
No. Repipes and water lines are PEX only.
Will you have to jackhammer my floors?
Not if we can tunnel a drain from outside or reroute a supply line through the attic or walls. Opening the slab shifts cost into flooring and dust; we use that only when the route requires it, and it will be on the written quote if it does.
Does homeowners insurance cover slab leaks in Texas?
Sometimes the damage and the access, often not the failed pipe itself, and policies differ. That is general information, not legal advice. Ask your agent. See the insurance section in our sewer cost guide for the short version.
Do you offer financing?
Yes. Financing is available, subject to credit approval. There is also 15% off when you approve your written quote the same day. We're open Monday through Saturday, 7 AM–7 PM, and closed Sunday.