Three Categories of Pipe Failure — and Why the Diagnosis Determines the Fix
You've been quoted a number that didn't come with an explanation. Or you've been watching a damp spot grow for six months and you're not sure what it means yet. Either way, the first thing worth knowing: not every pipe problem is the same problem.
Pipe failures fall into three categories. The fix is different for each. The cost is different. The urgency is different. And any company that gives you a quote without first telling you which category you're dealing with is skipping the part that matters most.
Pressure-Side: Supply Lines Under 40-80 PSI That Never Stop Pushing
Your supply lines carry water from the meter to every fixture in the house. They're under constant pressure — 40 to 80 PSI, 24 hours a day, whether you're running a faucet or not. When a supply line fails, water flows until someone shuts it off.
What fails and why:
- Polybutylene pipe — installed in Oklahoma homes from about 1978 to 1995 — degrades from the inside when exposed to chlorinated municipal water. The pipe looks fine from the outside. Inside, it's becoming brittle. When it fails, it doesn't leak. It shears. One moment you have a functioning supply line. The next you have water shooting from the wall.
- Copper supply lines under a slab expand and contract with temperature changes. Over 20 to 30 years, that thermal movement rubs the pipe against the aggregate beneath the concrete. The friction wears a hole the size of a pencil lead. You won't hear it. You'll see it on your water bill.
- Galvanized steel pipe corrodes from the inside, slowly narrowing the bore. Your water pressure drops. The water tastes metallic. Eventually the corrosion eats through and you have a leak in the wall behind the shower.
- CPVC — the cream-colored plastic pipe used in some 1990s and 2000s construction — becomes brittle with age. A pipe that flexed when it was new will snap like a dry stick at twenty years old. Sometimes it breaks when someone closes a door too hard in the next room. That's Joukowsky shock — a pressure spike from a sudden change in flow — and a brittle CPVC system can't absorb it.
What the fix looks like:
It depends entirely on the scope. A single failed fitting is a spot repair — we cut out the failure, replace the section with the correct material, and pressure test the result. If you have polybutylene throughout the house and it's starting to fail at multiple points, that's a genuine full-repipe conversation. We'll tell you which one you're looking at, and we'll show you the evidence.
Gravity-Side: Drain and Waste Lines Where Slope Is Everything
Drain, waste, and vent pipes don't operate under pressure. They rely on gravity — which means they rely on slope. IPC 704.1 requires a minimum fall of 1/4 inch per foot for pipes 3 inches and smaller. When that slope is off — because the house settled, because someone installed it wrong, because the ground shifted under the slab — waste doesn't clear. It accumulates. Roots find the moisture. Grease builds at the low points. The problems compound.
What fails and why:
- Cast iron drain pipe in pre-1970s Oklahoma homes corrodes from the inside. Hydrogen sulfide gas — a natural byproduct of sewage decomposition — attacks the bottom third of the pipe. Over decades, that acid etches a channel through the iron. The top of the pipe looks fine on camera. The bottom is gone. We've pulled cast iron pipe out of Oklahoma City homes where you could see daylight through the bottom and the top was still structurally sound.
- PVC drain pipes can shear at the point where they penetrate the slab. Soil movement — especially the expansive clay common in central Oklahoma — puts lateral stress on a rigid pipe at a rigid concrete interface. The pipe snaps. Sewage leaks into the soil beneath your foundation.
What the fix looks like:
A camera tells us exactly where the failure is and what caused it. Cast iron channeling typically requires section replacement — we cut out the corroded section and transition to Schedule 40 PVC with approved couplings. A sheared PVC pipe at the slab means a spot excavation through the concrete. We saw-cut, dig down, replace the section, backfill, and re-pour.
Structural: When the Leak Is Under the Slab and the Clock Is Running
Slab leaks sit at the intersection of plumbing and structural engineering. The leak itself is a pipe problem — a failed copper supply line or a cracked drain fitting beneath 4 to 6 inches of concrete. But the consequences are structural. Water under a slab erodes the supporting soil. Over weeks and months, voids form. The foundation settles unevenly. Cracks appear in the slab, in the drywall, around the door frames.
A slab leak that's been running for a month is a plumbing repair. A slab leak that's been running for a year is a plumbing repair plus a foundation remediation. The pipe fix is the same either way. The difference is what the delay cost you in soil and structural damage.
How you know it's happening:
Your water bill crept up and you told yourself it was the sprinklers. There's a warm spot on the floor that wasn't there before. The foundation has a hairline crack that's getting wider. The water meter spins when nothing is running.
What the fix looks like:
We start with electronic leak detection to isolate the location without opening the slab. Once located, we saw-cut the concrete, excavate to the pipe, repair or replace the section, pressure test, backfill with approved material, and re-pour the concrete. Oklahoma code (IPC 312.5) requires a hydrostatic pressure test before we close up any repair — that's not our policy, that's the law. We do it on every job because it proves the repair holds.
