Slab Leak Repair
Slab leak repair is less a technique than a decision. With the leak located and the line mapped, two roads open: cut the concrete at the mark and fix the pipe where it lies, or leave the buried run in place (capped, depressurized, retired) and route new pipe overhead through walls and ceilings. Each is the right answer to a different situation, and choosing on economics rather than habit is most of the value a good contractor brings.
This page covers that decision and the work either way. It assumes a located leak. If the spot is not yet marked, detection comes first; its page explains why repairing an unlocated slab leak is a contradiction in terms.
Common Causes
What shapes the repair-versus-reroute call:
- The leak's address. A defect near the slab edge under cheap flooring argues for direct access; one under the kitchen's stone tile or the home's only bathroom argues loudly for going around.
- The line's biography. First leak in a healthy copper run: repair the spot. Second or third pinhole in aging soft copper: the line is announcing a pattern, and rerouting retires the whole risk, not one symptom.
- What sits above. Flooring that cannot be matched, cabinetry, finished spaces. Restoration cost is the silent half of every through-slab estimate, and the half owners forget to compare.
- The route overhead. Reroutes need a viable path: attic, walls, chases. An easy path makes abandonment cheap insurance; a hostile one tilts the math back toward the saw.
How a Plumber Diagnoses the Problem
How each path actually runs:
- Through the slab. Flooring lifted, concrete opened at the mark, soil excavated to the line, the failed section cut out and replaced with new pipe and proper connections. Then the hole is packed, the concrete patched, and the flooring restored by its own trade.
- The reroute. The buried run depressurized and capped at both ends, new line run overhead in modern material, dropped down walls to the fixtures it serves. The slab never opens, and the failed pipe simply stops being plumbing.
- Partial repipes. The middle path: reroute the failing branch while sound branches stay. It is often the honest answer for a first repeat leak, and a scoped-down cousin of the whole-house conversation.
- Proof under pressure. Either way ends the same: system repressurized, meter still, pressure held over time. A slab repair is finished when the numbers say the loss is zero. The patch in the floor is just carpentry.
Frequently Asked Questions
Repair through the slab or reroute the line: which is better?
Whichever costs less in total honesty: pipe work plus concrete plus flooring restoration for direct access, versus pipe work plus wall patching for the reroute. First leak in sound pipe under modest flooring? Often through the slab. Repeat leaks, aging line, expensive floors? The reroute usually wins. It is arithmetic, not doctrine.
Does slab leak repair include concrete and flooring restoration?
Concrete patching typically yes; finish flooring is usually its own trade and line item, and the place estimates quietly diverge. The comparison between repair paths should always be made on the all-in number including restoration, which this page's decision framing insists on.
Do repeated slab leaks mean repiping is the better answer?
Often. A line producing its second or third pinhole is reporting its condition, not its luck. Rerouting the failing run (or repiping the affected zone) retires the whole risk at once; fixing pinholes one by one under concrete is the most expensive possible subscription. The pattern, not any single leak, makes the call.
How is the repaired line tested?
Under working pressure, against the meter: leak indicator still, pressure holding, and a re-check after the system has run. The verification happens before concrete and flooring close. Sealing an unproven repair under a floor is the one mistake this process is built to prevent.
Is leak detection included in the repair?
They are separate scopes on purpose: detection delivers the located, mapped leak; repair prices the decision that map enables. Many projects run them back-to-back with the same visit sequence, but an honest repair quote on an unlocated leak does not exist, which is why the pages, and the scopes, stay distinct.
Decide the Repair Path
Share the detection results (the mark, the line's route, hot or cold) plus the flooring above and the home's leak history.
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