What should I ask before hiring someone to repipe my house?

Start here, because the rest doesn't matter if this part is wrong.

• What's your ROC number? Arizona requires a contractor's ROC number on all written bids and estimates (A.R.S. 32-1124). Look it up and confirm the license is active and covers residential plumbing. Our guide on verifying a plumber's ROC license shows how.
• Who pulls the permit, and is it in the price? In Phoenix, a leak repair can be permit-exempt, but the city's code says that if a concealed water pipe "becomes defective and it becomes necessary to remove and replace the same with new material, such work shall be considered as new work and a permit shall be obtained and inspection made." A repipe is that kind of work.

The FTC lists a contractor who "asks you to get the required building permits" among the signs of a contractor you may not want to hire. A pro pulls the permit and schedules the inspection.

Most repipes today use PEX or copper. Both can be done well. Ask the plumber to explain the choice for your house, then dig into the details:

• Which PEX, and which fitting system? The Plastics Pipe Institute notes that PEX made by any approved crosslinking method "must meet the same qualification and performance requirements" of standards such as ASTM F876. The fitting system is a separate choice, so ask which one they use and whether it's the one the pipe maker specifies.
• How will you protect it from sun and heat? This one is very Phoenix. Uponor's installation guide rates some of its white PEX for only 1 month of UV exposure and says not to store its PEX outdoors. Ask how pipe is stored on site and how any run near a skylight, attic vent or outdoor wall is protected.
• How will it be supported? Uponor's guide lists a maximum horizontal support spacing of 32 inches for PEX 1 inch and smaller under the IPC and UPC. Ask how they'll meet it.
• Is everything certified lead free? Federal law defines lead free as a weighted average of 0.25% lead on wetted surfaces, and the EPA requires manufacturers and importers to certify their products. Ask for certified pipe, fittings and valves.

For the material decision itself, see PEX vs copper for a whole-house repipe.

Scope, access and schedule are where a repipe bid gets vague. Pin down each one.

### Which lines and valves get replaced?

"Whole-house" means different things to different contractors. Ask for the scope in writing, line by line:

1. 1Every hot and cold line, or only some? Ask which pipes stay and why.
2. 2Fixture shutoff valves and supply lines under sinks and toilets. New pipe feeding old valves leaves a weak spot.
3. 3Water heater connections, including the shutoff and any recirculation line. Ask how the new pipe connects at the heater. Uponor, for example, says its PEX is approved for direct connection to electric water heaters and power-vented gas water heaters "where allowed by local code." Other setups may need a different connection, so get the plan in writing.
4. 4The main line from the meter. Ask whether the bid includes the service line or stops at the house. If your service line is old too, ask about it now.
5. 5Hose bibs and the laundry box, which are easy to forget.

The FTC says a contract should include "what the contractor will and won't do." Scope is where most surprises come from.

### How will you get to the pipes, and who patches the walls?

Ask how many openings they expect, where, and who closes them. Then ask:

• Do you patch drywall, texture and paint, or just patch? Either answer is fine if it's written down.
• How do you protect floors and furniture, and who cleans up? The FTC suggests asking for a "broom clause" that makes the contractor responsible for all clean-up work, including spills and stains.
• What happens if you find a surprise? A hidden leak or damaged framing behind a wall can change the job. The FTC says the contract should explain how change orders are handled, since a change order could affect the project's cost and schedule.

### How long will we be without water?

Ask for the schedule and the water-off windows, day by day. A repipe is much easier to live with when you know when the water is off and when it comes back on. The FTC says a contract should include an estimated start and completion date, so get it in writing. Our page on how long a whole-house repipe takes covers the usual sequence.

### Will you pressure-test before the walls close?

Ask how and when the new piping is tested, and whether the city inspection happens before any wall is patched. Uponor's installation guide, for residential systems, says to pressurize the system to 25 psi above working pressure or 100 psi and to test in accordance with local code. A contractor who can walk you through the test step by step is a good sign. Ask to see the gauge, too. It's a fair request on a job this size.

This is where the FTC's guidance is most useful:

• Payment schedule. The FTC suggests limiting your down payment and tying payments to completion of defined amounts of work. It also says not to pay cash.
• Lien waivers. Unpaid subcontractors and suppliers may be able to file a mechanic's lien against your home. The FTC suggests asking the contractor, and every subcontractor and supplier, for a lien release or lien waiver before final payment.
• Materials list. The FTC says the contract should include "a detailed list of all materials including each product's color, model, size, and brand."
• Warranty. Ask what covers labor and what covers the pipe and fittings, and get the names of who honors each. The FTC recommends the contract spell out the length of the warranty and any limitations.
• Right to cancel. If you sign at home, the FTC says the contract should include a written statement of your right to cancel within three business days.

### What answers should make you walk away?

No ROC number on the bid. A request that you pull the permit. Pressure to decide on the spot. A demand for cash only, or for payment of everything up front. Each of those shows up on the FTC's list of warning signs or conflicts with Arizona's license rules. For general hiring questions, see questions to ask before hiring a plumber, and if your pipes keep springing pinholes, read leak repair vs a full repipe first.

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