Quick answer
- A plumbing permit is required to repipe a home
- Only approved materials (commonly copper or PEX) may be used
- New piping is pressure-tested and inspected before walls are closed
- Proper support, spacing, and routing are code requirements
- Local amendments vary — verify with your building department
When this applies
Whole-home and partial repipes
Replacing supply piping throughout the home — or a significant branch — needs a permit. Patching a single failed section is usually a repair, but recurring failures often mean it's time for a permitted repipe.
How it works
The rough-in inspection
Before any drywall goes back up, the inspector verifies the new piping: materials, support, routing, and a successful pressure test. This 'rough-in' step is why a permitted repipe protects you — problems are caught while everything is still open.
Materials and the final
Copper and PEX are the common approved choices, each with trade-offs. After patch and finish, a final inspection closes out the permit so your repipe is on record.
What to watch out for
Closing walls before inspection
Concealing new pipe before the rough-in inspection means it may have to be reopened — costly and avoidable. Permitted work follows the correct sequence.
Unapproved materials or poor support
Wrong fittings, missing support, or improper routing cause leaks and fail inspection. The permit process holds the work to code.
Repiping your home? We pull the permit and do it to code.
Frequently asked questions
Why does a repipe need an inspection before drywall?
The 'rough-in' inspection lets the inspector verify materials, support, and a pressure test while the piping is still visible. It's your protection that the work is sound before it's covered.
Copper or PEX — does the permit care?
Both are approved in California; the permit and inspection confirm whichever you choose is installed correctly. We'll walk you through the trade-offs for your home.
How long does a permitted repipe take?
Most homes are repiped in a few days, with inspections scheduled around the rough-in and final. We coordinate the timing so it stays efficient.
Keep exploring
Reviewed by John Stevenson Plumbing, Heating & Air. Based on California Plumbing Code requirements for water-supply repiping (approved materials, support, pressure testing, rough-in and final inspection) and our local repipe experience. Local amendments vary — confirm with your city or county building department. Last updated 2026-06-25.