Tools · Trade detailPlumbing · For homeowners + flippers

Plumbing repipe cost calculator

Pick the plumbing job you think you have, then check the pipe material and access flags. Galvanized, polybutylene, slab plumbing, low pressure, or a main-line scope can turn a small repair into a full-system planning number.

Planning math for homeowners and flippers — not a plumber’s bid, not a substitute for a licensed plumber.

Not sure what to enter? Open this 30-second checklist.

— Pipe material if you can see any (galvanized, copper, PEX, polybutylene, CPVC) — look at the water heater or basement ceiling.
— Where the pipes run: basement, crawl space, slab, or finished walls.
— Whether the issue is one leak, one room, the whole house, or the yard / service line.
— Whether water pressure is low or sputtering across the whole house.
— Whether leaks have repeated, or there are signs at ceilings / rim joists.
— Whether drains are cast iron (black, rust-flaked, often in the basement ceiling).
— Whether street-to-meter utility work may be involved.

Don’t have all of it yet? Start with what you know — the calculator’s defaults are conservative. Refine after the walkthrough.

Scope

Square footage

sqft

Your home's total floor area. Drives run-length derivation and $/sqft cross-check.

Fixture count

fixtures

Tubs, showers, lavs, water closets, kitchen sink, laundry, hose bibs. A 3-bed / 2-bath = 10-12 typical.

Bathrooms

bath

Proxy for branch zoning + drain-side load. Half-baths count as 0.5.

Supply pipe material

PEX A is the modern default — flexible, freeze-tolerant, single-tool installs. Copper Type L is 3-4× the cost but the lender / appraiser favorite on premium properties.

Estimated repipe budget

Feasibility budget: $7.3K–$12K

A planning estimate, not a contractor bid. Use this to decide whether to call plumbers for quotes.

$3.67–$5.89/sqft cross-check · mid $9.6K · 2,000 sqft · Full house repipe

Includes · supply piping, fittings, rough-ins, permit.

Excludes · wall repair on finished drywall ($1.5-3/sqft of affected area), fixture choice (toilet, vanity, faucet, valves bought separately), water heater replacement, and drain-only scope (this calc is supply-side primary).

Best next step · Get 2-3 bids from licensed plumbers.

Line breakdown · Full house repipe

Line item

Range (low — high)

Confidence

Supply piping (material + run length)

$3,966 — $5,706(mid $4,836)

Medium

▸ Operator note

744 lf at $4.5-$9.0/lf combined material + labor (pex-a).

Fittings + manifold

$443 — $637(mid $540)

Medium

▸ Operator note

Manifold + fittings scaled to 12 fixtures touched (pex-a).

Fixture rough-ins

$2,706 — $3,894(mid $3,300)

Medium

▸ Operator note

12 fixture rough-ins at $150-$400 each.

Permit + inspection

$225 — $275(mid $250)

High

3 lines not in this scope

Drain pipingnot in scope

—

Rough

Main line replacement + ROW permitnot in scope

—

Rough

Slab cut + repairnot in scope

—

High

Range low — high: $7.3K — $12K; mid $9.6K

Budget cushion

The math (mid estimate)$9.6K mid · $7.3K–$12K band on the recommended scope.

What I'd actually need before startingDon't start under $15K liquid + $2.5K reserve.

Why the cushionOn a repipe the walls don't tell you what's behind them until demo — a tested branch turns into a 6-fitting cascade once an inspector spots a lead-solder joint or you find galvanized you didn't see at walkthrough.

When NOT to over-padIf you're stretching to make the high band fit, you're flagging the deal isn't there. Walk the property with a plumber before tightening — better discipline doesn't close a deal that doesn't pencil.

Optional detailsmanagement, permit jurisdiction, known run length

Management

Permit jurisdiction

Known supply run length

If you've measured from manifold to farthest fixture and totaled the branches, enter the number. Leave blank to estimate from sqft + fixture count.

Risks you see during walkthroughoptional · tick what you actually see at supply stubs + mechanical room

Walk the basement or mechanical room and a few supply stubs, then tick what applies. Old galvanized or polybutylene supply lines usually push the project to a whole-house repipe; the other four widen the price band and surface inspection-time warnings. Defaults assume a clean property.

Galvanized supply lines presentOld steel supply pipe — usually means a whole-house repipe, not a spot fix.Polybutylene (PB) supply lines presentGray plastic supply line (often with metal-band clamps) — class-action history; whole-house repipe.Cast iron drain lines presentCast iron drain stack visible in the basement — may add drain replacement to the scope.Pre-1986 home (lead-solder potential)Built before 1986 — copper joints may use lead solder; budget for lead-free joint repair.Low / inconsistent water pressure historyWeak pressure or past pinhole leaks — widens the band; with galvanized, points to whole-house repipe.Slab foundationPipes run under a concrete slab — concrete cutting may be added to the bill.

How I’d actually use this on a flip

On a Chicago-metro deal, I run the gut rehab calc first to decide whether the property pencils overall. If the plumbing line on that breakdown is more than ~10% of hard cost, I drop into this calc and tighten the number. Square footage from the listing, fixture count from the floorplan, bath count from the photos, and I default the supply material to PEX-A until I see something in the basement that changes my mind. Leak flags stay off until the walkthrough.

Second pass is during the walkthrough. I put hands on the supply stubs at the water heater and at any exposed basement run. Gray, threaded, magnetic with a screwdriver tip stuck to it — that’s galvanized, and the calculator moves whatever scope I picked up to full-house repipe. Gray plastic with banded fittings (especially on a 1978-95 build year) — that’s polybutylene, and it does the same. Either flag flipped, and I’m re-baselining the deal on a 5-figure repipe instead of a 4-figure partial. The requested-scope dollars get replaced with the recommended-scope dollars — the number my offer has to survive when “the listing said updated plumbing” meets the systemic risk the property is showing.

A Michigan tax-deed property I picked up two years back is the cautionary tale here. Listing photos showed copper supply at the water heater; walkthrough showed copper for the first six feet, then galvanized everywhere downstream where I hadn’t looked. Calc would’ve flagged the same scope promotion the inspector eventually did. Now I budget repipes against the calc’s high band with every supply-side flag set before I write the offer, then relax flags only on what the walkthrough actually clears.

One leak or failing system?

Plumbing’s budget-killer is rarely the leak you can see — it’s what the visible leak says about the system behind walls, under slab, or in the yard. Six conditions move the calculator from the repair you hoped for to the system scope the house is really showing you. Each is framed as “what you see / what it means / what to do.” The first two are scope-changing on their own; the other four either change scope when combined with material flags or widen the price band and surface inspection-time warnings.

Galvanized supply lines.
What you see: threaded steel pipe at the water heater or basement ceiling, usually pre-1960 vintage. Pressure drops when more than one fixture runs.
What it means for budget:the calculator moves the scope up to full-house repipe. Galvanized fails systemically — one branch corroding through usually means the rest are on the same clock, and many Chicago-metro inspectors and plumbers price the project as a system risk rather than a one-room fix. Some insurers may flag old galvanized supply lines too, especially after repeated leaks or open claims.
What to do:plan full-house in your budget from the start; don’t price a partial. Combined with low-pressure history (pinhole-leak signature) or slab foundation (every leak becomes a slab-cut event), the urgency is higher. The galvanized-to-PEX conversion cost guide walks the per-fixture math and the wall-fishing labor that makes galvanized removal more expensive than a clean PEX install on the same plan.
Polybutylene (PB) supply lines.
What you see: gray flexible plastic pipe with banded metal fittings, 1978-1995 install era. PB-2110 stamping on the pipe.
What it means for budget: the calculator moves the scope up to full-house repipe. PB was the subject of the 1995 Cox v. Shell Oil Co. settlement for systemic acetal-fitting failures. Many homeowner-insurance carriers list PB as a non-renewable risk and may not quote without confirmed full replacement.
What to do:budget the full system from day one. Avoid partial PB-to-PEX transitions — the joints between old and new are chronic failure points. The polybutylene replacement cost guide walks the insurance angle plus the per-bath PEX retrofit math.
Cast iron drain lines.
What you see: black iron drain pipe (4-inch typical) visible in basement ceilings or crawl space. Rust-flaking or cracking on horizontal runs.
What it means for budget:warning only — the scope doesn’t change automatically. But if you open supply scope wide enough, the inspector may require companion drain-side replacement at the same time (drain code — UPC 609 in most Chicago-metro jurisdictions).
What to do:tick the cast-iron-drain flag so the calculator includes drain replacement in the band — you want both sides visible before you bid.
Pre-1986 home.
What you see: copper supply with soldered joints, built before the 1986 Safe Drinking Water Act lead ban took effect.
What it means for budget:any disturbed copper joint may need lead-free-solder remediation under the Safe Drinking Water Act 1986 amendments + EPA Lead and Copper Rule. Repair-only scope on pre-1986 commonly grows into partial-branch once the inspector arrives, so the calculator moves repair-only up to partial-branch. (Lead-solder rules live with the EPA and SDWA; system pressure testing under IPC 312 is a separate question and doesn’t govern lead chemistry.)
What to do: assume your repair-only budget will land at partial-branch numbers; rework the spreadsheet before bidding.
Slab foundation.
What you see: concrete slab without a basement or crawl space underneath. Supply lines buried in or under the slab.
What it means for budget:the calculator adds a slab-cut + repair line when scope is at partial-branch or above — each fixture access point is 2-4 sqft of slab opening at $40-90/sqft. On repair-only scope, the calculator surfaces a warning instead: leak detection typically requires acoustic + thermal locate ($300-800 separately).
What to do: get the locate cost line-itemed before committing to repair-only on a slab. If multiple access points are needed, full-house often pencils better than serial slab cuts.
Low / inconsistent water pressure (no visible galvanized).
What you see:pressure drops when multiple fixtures run, but the pipe material isn’t obviously galvanized.
What it means for budget:warning only — the scope doesn’t change automatically. But pressure history alone may still mean pinhole corrosion upstream. Even after a partial repipe, expect 3-6 month re-emergence risk on un-touched branches.
What to do: widen your contingency band by 10-15% on partial scope, or move to full-house if the property history suggests upstream corrosion.

Where the pipes are matters as much as what they are

The same scope can swing thousands of dollars on access alone. A full-house repipe in an open basement is a different project from the same repipe under a slab. Read your house against this ladder before you decide which scope to price.

Open basement or unfinished crawl space. Easiest access tier. Plumber routes new branches overhead through joist bays; no drywall is opened. Patch and paint stay out of the bid.
Finished walls and ceilings.Mid tier. Fish-through opens drywall at each branch entry and exit. Plumber bids the pipe work; you budget wall patch and paint separately at roughly $1.50–$3 per sq ft of affected wall.
Slab foundation.High tier. Supply lines are buried in or under concrete. Plumbers either reroute overhead (lose ceiling height) or cut and patch the slab (2–4 sqft per fixture access point at $40–$90/sqft). On a slab leak, an acoustic + thermal locate ($300–$800) runs separately before anyone cuts.
Yard / main line (street to meter to house). Highest tier. Trench work, right-of-way permits, and a utility quote for the street side. Street-to-meter is utility/municipal territory; meter-to-house is homeowner. The calculator can price the interior side; the utility side needs your utility’s rate sheet before you commit. The main water line replacement cost guide walks the trench math, the ROW permit, and the jurisdiction split.

Worked example — 1950s house with galvanized supply and low pressure

You walk a 1955 ranch listing, ~1,500 sq ft, three bedrooms, two baths. The kitchen sink trickles when the shower runs; the basement ceiling shows gray, threaded steel pipe at the water heater. The seller said they replaced “some plumbing.” You assume a partial-branch on the kitchen side will fix the pressure issue.

Scope you picked: Partial branch.
Flags ticked: Galvanized supply, low-pressure history.
Recommended scope:Full-house repipe (or galvanized-to-PEX — same number, different label).
Why it changed:Low pressure with visible galvanized is the textbook pinhole-corrosion signature — the kitchen branch isn’t the only branch on the same clock. Pricing a partial here leaves the other branches on the same failure curve, which can turn into serial repairs over the next few years, and the inspector will often require a system-wide approach once they see the material.
What to ask the plumber:“Are you pricing a patch on the kitchen branch, a partial repipe on the wet wall, or a full conversion to PEX?” The answer tells you which planning band on the calculator is the real one. The how much does it cost to repipe a house guide walks the per-fixture math in prose if you want the cost picture without the scope logic.

A second pattern worth flagging: if the scope you actually need is on the yard / service line (not interior), the calculator’s interior estimate is fine for budgeting one side — but ask the utility where homeowner responsibility starts before you commit. That boundary varies by utility and municipality, and the street-side bill is theirs to set, not the plumber’s.

Methodology

Every dollar number on this page traces to one of three layers: SiteworkMath planning ranges (anchored on Uponor / SharkBite / Apollo PEX A/B spec sheets, copper Type L mill data, CPVC manufacturer specs, MCAA labor units where citable, and Chicago-metro 2024-2026 permit fee schedules), code references (UPC 2024 §604 water distribution, §605 PEX install, §609 drain pipe; IPC 2024 §312 testing requirements, §605 backflow protection — cited inline in the inspection-warning panel), and operator calibration on Chicago-metro permit-tier behavior. The full per-calculator sourcing tier in methodology spells out which sources back which kinds of claims. The numbers are planning ranges, not contractor bids — the feasibility caveat is part of the calculator output for that reason.

Show the formulas

Supply piping: runLengthLf × $/lf × labMult. Run length derives from sqft × 0.3 + fixtureCount × 12 on full-house; ~40% of that on partial-branch; 10 lf on repair-only. PEX A/B ~$4-9/lf combined; copper Type L ~$14-32/lf; CPVC ~$6-14/lf. Owner-with-permit multiplier 0.75× labor.
Fittings + manifold: basePrice × max(0.5, fixtureCount/10) × labMult. PEX A/B manifold $250-700 mid base; copper soldered $700-1700 mid base (~2.5× PEX). Scales with fixture count touched.
Fixture rough-ins: fixtureCount × $150-400 × labMult. Includes valve, drop, escutcheon, supply stub per fixture. Excludes the fixture itself.
Drain piping (conditional): Active on full-house scope, or any scope when castIronDrain flag set. Length scales with bath count (25 lf/bath + 30 baseline). Cast iron ~$55-110/lf combined; PVC schedule 40 ~$14-28/lf. Governed by UPC 609.
Main line + ROW permit (conditional): Active onlywhen main-line scope is explicitly selected. Full-house repipe does NOT include the street / utility-side service line by default — if you need both interior repipe and main-line replacement, run the calc twice (once per scope) and add the totals. Trench length 60-150 lf typical Chicago-metro lot. $80-160/lf material+labor plus Chicago-metro ROW permit $1500-5000 fixed adder. The main-line scope surfaces a separate warning banner because the utility-side cost is jurisdictional and can’t be priced from this calc.
Slab cut + repair (conditional): Active when slabFoundation flag set + scope at partial-branch or above. accessPoints × 3 sqft × $40-90/sqft × labMult. Access points scale with fixture count touched (60% on full-house; 30% on partial; 1 on main-line).
Permit + inspection: fast $50-200 / typical $100-400 / strict $300-1200 mid. Strict-tier is Chicago-metro Oak Park / Evanston / Wilmette baseline (~3× typical mid).
Confidence band: high ±10% / medium ±18% / rough ±32%, plus ±4% per active leak flag.
Scope promotion: galvanized OR polybutylene promotes any non-full scope to full-house repipe; pre-1986 + repair-only promotes to partial-branch. Reality checks (cast iron drain, low pressure without galvanized, slab + repair-only) surface as warnings without promoting scope.
Engine logic: lib/sitework/plumbing/plumbing.ts with pricing anchors in defaults.ts and types in types.ts. Tested in plumbing.test.ts.

Frequently asked

What does this plumbing repipe cost calculator estimate?

A planning-range budget for residential supply-side plumbing — the number you'd use to decide whether to call a licensed plumber at all. Not a plumber's bid. It covers plumber labor, supply pipe and fittings, fixture rough-ins, permit and inspection, drain piping when cast-iron drain is flagged, and slab access when slab foundation is flagged. What sits outside the number: the fixtures themselves (toilet, vanity, faucet trim), water-heater replacement, drain-only scopes, wall patch and paint after fish-throughs (budget $1.50-$3 per sq ft separately), and HVAC re-routing.

Why does this calculator have five scope modes instead of one repipe estimate?

Because the dollars and the inspection consequences are different across the five. Cost-guide aggregators flatten them into one per-fixture or per-sqft number, which buries the question that actually decides the budget: which scope is the house actually a candidate for? The five modes are full-house repipe (every supply branch), partial branch (one zone or bathroom), main line (street-to-meter or meter-to-manifold), galvanized-to-PEX (material conversion across all branches), and repair-only (a targeted 5-15 ft leak section). Why scope can move up: a galvanized system rarely passes inspection at partial-branch in most Chicago-metro jurisdictions — the inspector will usually require full-house. The calc returns the line set for the scope the inspector will accept.

What does 'scope promoted' mean in the inspection warning?

The calculator returned a different scope than the one you asked for, because a supply-side property flag makes the smaller job unrealistic. Galvanized supply pipe and polybutylene (PB) both move the scope up to full-house — galvanized fails systemically, and many insurance carriers list PB as a non-renewable risk after the 1990s class-action settlement. Galvanized plus a slab foundation adds a slab-cut line. Galvanized plus low-pressure history is the textbook pinhole signature. Pre-1986 plus repair-only moves to partial-branch: copper joints from before 1986 may use lead solder, which the 1986 Safe Drinking Water Act amendments require swapping out. The inspection-warning panel above the dollar output spells out the rule that fired.

Why does the main-line replacement scope warn about a separate quote?

Because main-line work straddles two jurisdictions that get flattened into one cost-guide number. The street-to-meter side is utility / municipal territory. The utility either does the tap themselves or requires a contractor on their pre-approved list. The price is set by their schedule and crew rates, not the open plumbing market. The meter-to-manifold side is homeowner territory and prices like normal trench plumbing. This calc estimates the interior-side line plus the right-of-way permit adder. The utility-side quote has to come from the utility's rate sheet — skipping that step is how main-line projects double in budget after the contract's signed.

What's the difference between this calc and a plumber's bid?

A plumber's bid prices the specific scope on the specific property with the specific access conditions. This calc prices the scope category on a typical property in your jurisdiction tier. Use the calc to decide whether the project is worth calling plumbers at all. Use the bid for the contract number you'll sign. On a flip I run this calc on the property photos before I even submit an offer, then drop into a plumber bid only after the property survives the calc's high band.

What's NOT included in this calc?

The pipe, fittings, labor, permit, and code-driven upgrades are in. Fixture brands, water heaters, drain-only scopes, and wall patching are out. Fixtures vary 5-10× across consumer / builder / luxury tiers — budget separately. Water-heater replacement is its own $3K-$8K category. Drain piping activates only with the cast-iron flag or full-house scope. Wall patch runs $1.50-$3 per sq ft, outside the plumber's bid. The contingency band absorbs code-required upgrades the calc can't see — water shut-off, expansion tank, pressure-reducing valve, backflow preventer.

What I’d do next

Plug this number into the gut-rehab feasibility calc
If the plumbing scope is one line on a larger rehab, take the mid from this calc and override the plumbing line on the gut-rehab cost calc.
Sequence the repipe against demo, drywall, and inspection gates
Plumbing rough-in is gated by demo and frame inspections, and gates drywall on the back end alongside electrical. The timeline calc shows the critical-path slot.
Read the planning-range methodology
What's anchored, what's a planning range, and how the manufacturer-spec + MCAA + permit-fee cross-check works against operator calibration.

By James Wu. Pricing anchors: Uponor / SharkBite / Apollo PEX A/B spec sheets, copper Type L mill data, CPVC manufacturer specs, MCAA labor units where citable, Chicago-metro 2024-2026 permit fee schedules. Code references: UPC 2024 §604 (water distribution sizing), §605 (PEX install), §609 (drain pipe); IPC 2024 §312 (system pressure testing), §605 (backflow protection). Lead-solder remediation on pre-1986 joints is driven by the Safe Drinking Water Act 1986 amendments + EPA Lead and Copper Rule (LCRR), not IPC 312. Engine logic in lib/sitework/plumbing/plumbing.ts. Numbers are SiteworkMath planning ranges, not contractor bids — feasibility framing is part of the output for that reason. Not a substitute for a licensed plumber’s site visit. Full methodology.

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Hi, I'm the SiteworkMath assistant. I answer questions about the calculators and guides on this site — concrete yardage, topsoil, mulch, tile, and decking material math. I'm not a structural engineer or a licensed contractor; I'm a calculator built around the math that James Wu — Chicago-area flipper — uses on his own jobs. For structural decisions (joist sizing, beam spans, footing depth in your soil + climate, anything that needs a permit) talk to a licensed structural engineer or your local building department.