Whole House Repipe

Repiping means pulling out the supply piping that feeds every fixture and running new. It is the biggest plumbing job a homeowner ever signs off on, and the one most often sold on a hunch about the year the house was built. Sometimes the real answer is one bad section and a worn pressure-reducing valve, the regulator that sets house pressure where the water comes in.

Three things justify it. A longer list does not.

A repipe earns its keep in three situations. The pipe is a product with a known failure history, which means polybutylene. The pipe is corroding from the inside so the bore is closing, which means galvanised steel. Or pinholes keep appearing in several different runs, which says the pipe is the problem and not one overtightened fitting.

What does not justify it on its own: one leak, a joint that weeps, or rusty water for a minute after the utility flushes a main. Pressure that dropped everywhere is usually that valve, or a main shutoff nobody opened all the way. That is an afternoon.

Galvanised steel: forget the lifespan number

Nearly every plumbing site says galvanised pipe lasts 40 to 50 years. Nothing is behind that figure. It is not in InterNACHI’s life expectancy chart, which has no galvanised row at all, nor in EPA’s distribution system paper. Two peer-reviewed studies decline to give a number and one concludes that galvanising thickness alone does not ensure longevity.

The mechanism is more useful. The pipe is steel under a zinc coating of roughly 40 to 55 micrometres. Water consumes the zinc, the bare steel corrodes, and the corrosion product builds back onto the wall as lumps called tubercles, with deep pits underneath them. EPA describes the same process in water mains and lists what people notice: more leaks, bad taste and odour, red water. The bore closes as the scale grows inward, so pressure falls.

The era is the stronger argument and it is sourced. InterNACHI says galvanised steel was common until the 1950s, so anything still in service has been in those walls past seventy years. Our pipe materials by decade page covers what is in a house of a given vintage.

Polybutylene, and the thing nobody can tell you

Polybutylene was made from 1978 to mid-1995, with production stopping in mid-1996. It is usually stamped PB2110 and most commonly grey, though white, silver, black and blue exist. The stamp and the colour you can check yourself, with a torch in the crawl space.

Why it matters is on the public record. In 1995 a Tennessee court approved a national class action settlement in Cox v. Shell Oil under which Shell and Hoechst contributed $950 million to replumb leaking polybutylene systems, per a Fifth Circuit opinion. The South Carolina Supreme Court records that Celanese and DuPont produced the acetal fittings (Celcon and Delrin) moulded into the joints. Plaintiffs alleged the resin was marketed with a 50-year life while company scientists had reported it would degrade at ordinary chlorine levels. Allegations a court recited are not findings.

Now the part worth knowing before you pay anyone to assess it. No inspection clears polybutylene. InterNACHI is explicit that no tests for weakness should be attempted, because deterioration starts inside the pipe wall and cannot be found without shutting the water off and dismantling it. An inspector can confirm you have it. Nobody can grade it. That asymmetry is the argument for replacing it before it decides the timing for you.

Copper pinholes are a water problem, not an age problem

A Virginia Tech master’s thesis on copper pitting, written under Marc Edwards, reports that in 2004 it was unambiguously proven that water alone could eat a pinhole through copper tube, with no defect and no installation error needed. Treatment changes linked to outbreaks include higher pH and higher chlorine residuals. One outbreak at a large Maryland utility caused leaks in 20 to 50% of the homes it served. That is a thesis rather than a peer-reviewed paper, and we say so.

A peer-reviewed study of Santa Fe tube that leaked after fifteen years found microbes wedged deep inside the pits, and noted that older homes nearby, on the same supply water, had not suffered the same leaks. Same water, same street, different outcome. Which is why our leak detection work starts by cutting out a sample.

What the sources actually say, material by material

Material	Era	What a real source says about life	How it fails
Galvanised steel	Common until the 1950s	No authoritative figure exists. InterNACHI’s chart has no row for it, and a peer-reviewed study concludes galvanising thickness alone does not ensure longevity.	Zinc depletes, steel corrodes, tubercles build inward and close the bore. Pressure falls and the water runs rusty.
Polybutylene	1978 to mid-1995, production ending mid-1996. Stamped PB2110, usually grey.	Nothing usable. A 50-year claim appears only as a plaintiff allegation recited in court opinions.	Oxidants in the supply react with pipe and fittings, which scale, flake and crack from inside. The acetal fittings were implicated in the Cox settlement. No test can grade a run in place.
Copper	In water service since the 1930s. Type K thickest and used underground, Type L the high-quality grade, Type M thinnest and most common indoors. Markings are green for K, blue for L, red for M.	Roughly 50 to 70 years per InterNACHI, whose own chart carries both numbers and disclaims them as guidelines rather than warranties.	Pitting driven by water chemistry, not by age. Type M has the thinnest wall, so less metal to get through before a pinhole. No source gives Type M a shorter service life.
CPVC	Still installed	Well in excess of 50 years per the Plastics Pipe Institute, conditioned on correct specification and installation.	Stress cracking where an incompatible product touched it. Not chlorine.
PEX	Still installed	40 years per InterNACHI, against a 50-year minimum extrapolated lifetime from the accelerated lab test in ASTM F2023 per the Plastics Pipe Institute. Different measurements, so they do not average.	UV exposure, with limits published per manufacturer and indirect light counting. Historically the fittings rather than the pipe: high-zinc yellow brass can shed its zinc and go porous.

Copper or PEX, and why the fittings decide it

Both are approved and we fit both. The lifespan column does not settle it, because InterNACHI’s field estimate and PPI’s extrapolated lab minimum are not measuring the same thing, and InterNACHI’s two copper rows disagree with each other inside one chart. Look at the failure column instead. A Penn State engineering case study, student work rather than peer-reviewed, walks the PEX pattern: high-zinc brass fittings shedding zinc, going porous, leaking. Same lesson polybutylene taught. These systems fail at the joint, which is why how a house is piped matters more than which material is on the invoice.

Two practical notes. PPI says each PEX manufacturer publishes its own maximum UV exposure limit and that indirect light counts, so pipe left permanently exposed in an unfinished basement gets covered. And copper markings are worth learning: green for Type K, blue for Type L, red for Type M.

The inspection sets your schedule, not the drywall crew

A repipe needs a permit. The 2021 Virginia Uniform Statewide Building Code, effective January 18, 2024, requires one before any alteration involving the water supply and distribution system, at Section 108.1. The ordinary-repairs exemption covers a like-for-like fixture swap that leaves the piping alone, which is the opposite of a repipe.

Then the sequence, which is the most practical thing to understand before you book a painter. Section 113.3 lists the minimum inspections and item five is inspection of plumbing systems prior to concealment. That is the rough-in. Section 113.6 says defective work must be corrected and reinspected before anything conceals it, and a final inspection follows at completion. New pipe in, pressure tested, the county looks while it is open, and only then does drywall close. A contractor offering to close the walls first is offering to open them again.

So a real schedule has a gap in the middle of it. Prince William County wants inspections scheduled by 3 p.m. the working day before, then emails a two-hour arrival window. Fairfax County takes requests up to 11:59 p.m. for the next business day. Section 113.7 is the backstop: if the building official cannot inspect within two working days, third-party reports have to be accepted for review.

On fees, Section 107.1 leaves the schedule to the local governing body, which is why Woodbridge and Alexandria differ. The only statewide piece is a 2.0% levy funding the Virginia Building Code Academy, so there is no state permit fee for a repipe. If the job takes in the line from the meter, Prince William County publishes a residential water service permit at $110.65 including surcharges, effective July 1, 2026, and Fairfax County lists water service at $77.70 against a $141.75 base minimum plus a 10% surcharge. See water line replacement.

Three code items that catch people mid-repipe

• Thermal expansion control. Code P2903.4 requires a means of controlling the pressure rise from thermal expansion where the service carries a pressure-reducing valve, or a check valve with storage water heating. The house is then a closed system and expanding hot water has nowhere to push. Static pressure is capped at 80 psi.
• Water hammer arrestors. Virginia amends the code at P2903.5 to require an arrestor conforming to ASSE 1010 where quick-closing valves are used, meaning washer and dishwasher solenoids. The walls are open anyway, so this is the cheapest it will ever be.
• Pipe in cold places. P2603.5 bars water pipe in an attic or crawl space subject to freezing unless it is protected by insulation or heat. If your old pipe split, routing matters as much as material: see burst and frozen pipe repair.

How the job actually runs

1. Identify the pipe, not the decadePolybutylene means hunting for the stamp. Galvanised means cutting a sample, because the bore is the argument.
2. Permit firstOur licence number goes on the application before a pipe moves, under Section 108.4.
3. Open only what has to openAccess cuts rather than demolition. PEX bends, so it needs fewer openings than copper.
4. New supply, shutoffs and supportWorking shutoffs at the fixtures and correct support, so nothing drums when a valve closes.
5. Pressure test, then the inspectionTested while everything is visible, then the rough-in. Nothing is covered before sign-off.
6. Close and finishDrywall patched to the standard written into the quote. Ask every bidder what that standard is.

When we tell people not to repipe

We have talked homeowners out of this job. A nineties house with copper and one weeping joint needs that joint and a pressure check, not a week of open walls. A pipe that split in a cold snap needs the pipe repaired and the crawl space dealt with. The test is whether the material itself is finished.

Virginia Class A contractor licence #2705131990. Under 18VAC50-22-61 a company cannot hold the plumbing classification unless a master plumber qualifies the licence, which says more than a badge on a van. Family run, 40-plus years in the trade. A person answers at (703) 491-6542 during office hours and Jon takes the after-hours calls himself, though we will not promise a truck at 3am.

Common Questions