# Partial Repiping in Philadelphia

> Partial repiping in Philadelphia homes: one bathroom, one riser or the hot side replaced, with the boundary, transitions and remaining old pipe in writing.

URL: https://philadelphiafreedomrepipe.com/partial-repiping/

Part of the supply system replaced, such as one bathroom group, one riser, the basement main or the hot side, with a written boundary and a list of the old pipe that stays.

Last Updated: October 26, 2026

**223** L&I permits over 36 months to replace the supply lines for a named fixture group such as a bathroom or kitchen

**52** Whole-house or explicit water piping replacement permits over the same 36 months

**$37** L&I repair or replacement fee for water lines in a one- or two-family dwelling; $126 in other occupancies

[Philadelphia Freedom Repipe](https://philadelphiafreedomrepipe.com/) replaces part of a house’s water supply piping when only part of it needs to go: one bathroom group, one riser, the basement main or the hot side alone. That can be the right scope. It can also be a way of paying for openings twice. What makes a partial repipe sound is a clear boundary, a good joint at every point where new meets old, and an honest written record of the old pipe still in service. Licensed and insured contractors carry out the work; inside the city, a Philadelphia licensed master plumber oversees the job and pulls the L&I permit.

A partial repipe is not a [whole-house repipe](https://philadelphiafreedomrepipe.com/whole-house-repiping/), and the paperwork should never blur the two. A house with a new bathroom branch and decades-old steel everywhere else is partly repiped, and it should be described that way to the owner, the inspector and any future buyer.

## Defining the boundary

Every partial repipe starts with the whole system, not only the part that is failing. The walk-through traces the pipe from the main shutoff to each floor, records the material on every run, marks earlier repairs and reads pressure and flow. Only then can a boundary be drawn in the right place.

A good boundary follows the way water moves. It starts at a point where the pipe upstream is sound enough to keep in service, such as a copper main that was replaced years ago or a riser that still flows well, and ends at the fixtures. A boundary drawn in the middle of corroded steel just moves the next leak a few feet down the line. Where the boundary falls, a shutoff often goes in too, so the old section can be isolated later without shutting down the whole house.

The written scope names the boundary by room and line: “hot and cold from the basement main tee to the second-floor bathroom fixtures”, not “upstairs plumbing”. L&I’s permit records show this kind of job is common. Over 36 months, 223 permits replaced the supply lines for a named fixture group such as a bathroom or kitchen, against 52 whole-house or explicit water piping replacements.

## What stays, and why it goes in writing

Retained pipe is the part of a partial job that people forget. A partial repipe leaves old pipe in service by definition, and that pipe keeps aging. The quote and the closing paperwork should list each run that stays, its material, where it is and how it connects to the new work. That record does three things. It keeps the owner from believing the house is fully repiped. It tells the next plumber which pipe is old before they open a wall. And it answers the question a buyer’s inspector will ask. The guide to [buying a Philadelphia house with old pipes](https://philadelphiafreedomrepipe.com/guide/buying-a-philadelphia-house-with-old-pipes/) shows why that matters at sale.

## Transitions between new and old

Every boundary is a joint between two materials, and those joints need care. Copper joined to galvanized steel needs a listed dielectric union or a brass or bronze fitting between them, because the two metals touching in water speed corrosion of the steel. PEX joins steel or copper through a listed brass adapter. In either case the joint is made on sound pipe: the old side is cut back past corroded fittings, and a fresh thread or a clean end is made.

Disturbing old pipe has side effects. Cutting into galvanized steel shakes loose scale that can travel downstream, and turning old fittings can crack the next joint. A partial repipe plan accounts for that with flushing after the cutover, a check of aerators and valves, and a look at the old joints nearest the boundary. The [galvanized pipe replacement](https://philadelphiafreedomrepipe.com/galvanized-pipe-replacement/) page covers transitions to steel in more detail.

## When partial makes sense

A partial repipe tends to fit when the trouble is clearly local and the rest of the system is in reasonable shape:

- **One bathroom during a remodel.** The walls are open anyway, so replacing the branch lines costs little extra in openings, and the riser feeding the room flows well.
- **One riser in a house or small building.** A single vertical run is restricted or leaking while the basement main has already been replaced. In multi-unit buildings this is the stack-by-stack approach covered on the [multi-unit repiping](https://philadelphiafreedomrepipe.com/multi-unit-repiping/) page.
- **The basement main.** The basement main carries all the water the house uses, so restriction there is felt at every fixture, and with the joists open it is the least disruptive part to replace, often paired with a new main shutoff.
- **Hot side only.** In galvanized houses the hot lines often corrode faster than the cold, because heat speeds the reaction. Replacing the hot side can restore hot-water flow while the cold side keeps working for now.

## When it does not

A partial repipe is the wrong scope when corrosion is spread through the house, when leaks keep moving from room to room, or when the boundary would leave restricted pipe upstream of the new work. New pipe downstream of choked steel still gets choked water, so a new bathroom fed by a corroded riser will not flow better. In those cases the money goes into openings and transitions that a whole-house repipe would have covered once, and the owner faces the same openings again later. The [guide to low water pressure in Philadelphia](https://philadelphiafreedomrepipe.com/guide/low-water-pressure-philadelphia/) explains why pressure problems often sit upstream of where they show.

Low flow can also come from outside the pipe entirely: a small or corroded service line, a main shutoff that restricts flow, a pressure-reducing valve or clogged fixtures. Those are checked before any boundary is drawn, and a partial repipe is not sold as a pressure fix.

## Permit, testing and pricing

Replacing water piping in Philadelphia needs an L&I permit. For a one- or two-family dwelling, L&I lists $37 for repair or replacement of water lines with no fixtures, or $126 in other occupancies; work that adds or reconnects fixtures may fall under the alteration fee instead, and the [Philadelphia repipe permit guide](https://philadelphiafreedomrepipe.com/guide/philadelphia-repipe-permit/) explains the difference. The new section is pressure tested before walls close, and the old pipe it connects to is checked for leaks at the new joints.

There is no published price range for partial repiping, because the boundary differs on every job. Length of pipe replaced, fixtures served, floors climbed, transitions, plaster or tile access and patching set the price. The [repiping cost guide for Philadelphia](https://philadelphiafreedomrepipe.com/guide/repiping-cost-philadelphia/) compares partial and whole-house scopes by driver.

## Related resources

- [How to identify your water pipes](https://philadelphiafreedomrepipe.com/guide/how-to-identify-your-water-pipes/) before deciding what stays
- [Repipe vs pipe lining](https://philadelphiafreedomrepipe.com/guide/repipe-vs-pipe-lining/) for sections that are not yet leaking
- [Do I need a repipe?](https://philadelphiafreedomrepipe.com/tools/do-i-need-a-repipe/), a short check of the signs
- [PEX repiping](https://philadelphiafreedomrepipe.com/pex-repiping/) for the material most partial jobs use

## What's included

- A survey of the whole system, not only the part being replaced
- A written boundary: where new pipe starts and stops, by room and by line
- New pipe in PEX or copper, as the code and the building allow
- A listed transition at every point where new meets old, made on sound pipe
- A shutoff at the boundary where it helps isolate the old section later
- Pressure test of the new section and a check of the old pipe it connects to
- Flushing after cutover and a check of aerators and valves downstream
- A written list of the old pipe left in service and where it is

## Partial repipe compared with a whole-house repipe

|  | Partial repipe | Whole-house repipe |
| --- | --- | --- |
| What is replaced | One defined part: a bathroom group, a riser, the basement main or the hot side | Every hot and cold supply line from the main shutoff to the fixtures |
| Old pipe left in service | Yes, listed in the scope with its location | None; abandoned pipe in walls is disconnected |
| Transitions | At every boundary; each is a joint between different materials | Only at the main shutoff and the water heater |
| Flow | Improves only the replaced part; restricted pipe upstream still limits it | Removes restriction inside the house; service line, shutoff and fixtures still count |
| Future work | The rest of the system will need attention later | No supply pipe left to replace |
| Pricing | No published range; priced from the boundary, openings and transitions | $4,000 to $15,000+ area range |

## Guides for this work

- Cost Guide [How Much Does Repiping Cost in Philadelphia?](https://philadelphiafreedomrepipe.com/guide/repiping-cost-philadelphia/)Typical ranges for a whole-house and a PEX repipe, what sits inside the price, the City's permit fees, and why two quotes for the same rowhouse can differ.
- Learn [Why Is the Water Pressure Low in My Philadelphia House?](https://philadelphiafreedomrepipe.com/guide/low-water-pressure-philadelphia/)Low pressure in an older Philadelphia house has several possible causes along the line from the street to the tap. How to tell a service line problem from an interior restriction, a valve or a fixture, and when a repipe actually helps.
- Learn [How Do You Identify the Water Pipes in Your House?](https://philadelphiafreedomrepipe.com/guide/how-to-identify-your-water-pipes/)A step-by-step way to tell galvanized steel, copper, lead, PEX, CPVC and polybutylene apart, using a coin, a magnet and the printing on the pipe, and where to find each run in a Philadelphia rowhouse.
- Decision Guide [Should You Repipe or Line Your Water Supply Pipes?](https://philadelphiafreedomrepipe.com/guide/repipe-vs-pipe-lining/)Epoxy lining coats the inside of the pipe you have; a repipe replaces it. What each method does, where lining can make sense, where its limits show up in old Philadelphia houses, and how to compare the two honestly.
- Learn [Do You Need a Permit to Repipe a House in Philadelphia?](https://philadelphiafreedomrepipe.com/guide/philadelphia-repipe-permit/)How the L&I plumbing permit works for a repipe in Philadelphia: when one is needed, who can apply, what the EZ permit covers, the published fee lines and surcharges, and what happens at inspection.

## 

1. First call You describe the house: rowhouse, twin or detached, how many floors and bathrooms, what the pipe looks like where you can see it, and what made you call. That sets up the walk-through.
2. Assessment The walk-through starts at the meter and main shutoff, traces the pipe up every floor, checks pressure and flow, and maps the routes and the openings. You get a written scope that says what is replaced and what stays.
3. The work A licensed master plumber pulls the L&I permit. New lines go in while the old ones keep the house running, then each section is cut over during a planned water-off window.
4. Completion The new piping is pressure tested and inspected, then flushed. Shutoffs are labeled, openings are closed to the finish the quote names, and you get a list of anything old that stayed in service.

## What this work looks like

Older copper pipe joined to new copper pipe with a brass coupling and a tag at the joint along basement joists

A bathroom wall opened above a pedestal sink showing new red and blue PEX lines to two shutoff valves

A water heater in a basement with new copper hot water piping rising to the joists

An opened pipe chase in a hallway showing copper risers in a small building

## Partial repiping questions

### What should a partial repipe quote say about the pipe that stays?

Where it is, what it is made of and roughly what condition it is in. The quote should name the boundary by room and line, list each transition between new and old pipe, and say plainly that the house is partly repiped. That record matters to the next plumber and to anyone buying the house.

### Is it worth replacing only the hot water lines?

Sometimes. In galvanized houses the hot side often corrodes faster, because heat speeds the reaction, so the hot lines can be clearly worse while the cold side still flows. Replacing the hot side solves that part. The cold side keeps aging, though, and a second job later repeats many of the same openings.

### Can one bathroom be repiped without touching the rest of the house?

Yes, if the pipe feeding it is sound. A bathroom repipe replaces the branch lines from where they leave the riser or main to each fixture, usually during a remodel when walls are already open. If the riser or basement main is badly restricted, the new bathroom still gets restricted water, so the feed is checked first.

### When is a partial repipe the wrong choice?

When corrosion is spread through the house, when leaks keep moving from one spot to another, or when the boundary would leave restricted pipe upstream of the new work. In those cases a partial job spends money on openings and transitions that a whole-house repipe would have covered once.

### How is a partial repipe priced without a standard range?

From the scope. The length of pipe replaced, the number of fixtures on it, the floors it climbs, the number of transitions, plaster or tile in the way and the patching that follows set the price. There is no published Philadelphia range for partial work because the boundary differs on every job.

## Related services

### Whole-house repiping

Every hot and cold supply line from the main shutoff to the fixtures, replaced in the material the Philadelphia code allows for the building and pressure tested before the walls close.

### Galvanized pipe replacement

Corroded steel water lines taken out of service, replaced in PEX or copper, joined to anything that stays with a listed transition, then flushed so loosened scale does not end up in the faucets.

### Multi-unit repiping

Supply risers and the branches into each apartment replaced one stack at a time, with water-off windows planned around the people living there and the material the code allows for the building.