Repiping in San Rafael and Marin County
We replace old galvanized and failing water lines, main service lines, and drain and sewer pipe in homes across Marin County and southern Sonoma County. A lot of Marin homes sit over a crawl space, so we can often swap pipe from underneath without opening up your walls. Every repipe is quoted as one flat price after an inspection, and the diagnostic visit is $69. California C36 license #1090862.
- Plumbing in Marin County since 2017
- California C36 plumbing license #1090862
- 5.0 stars from 89 reviews, as of October 2026
What's included
Included in every repipe
- An inspection of what's there now: pipe type, condition and water pressure
- A written scope and one flat price before we start
- Removal of the old pipe and new lines run to every fixture in the scope
- New shutoff valves where they're needed
- A pressure test of the new lines before we leave
- All rough materials from a plumbing supply house
Priced separately
- Drywall and finish repair where a wall has to be opened
- Main service line from the meter to the house, quoted separately
- Permits where the city requires them
- New fixtures at the same time, see kitchen and bathroom remodeling
Price guide
| Job | Price |
|---|---|
| Diagnostic visit, inspection and quote | $69 |
| Partial repipe, one area or one line | Quoted after inspection |
| Whole house water repipe | Quoted after inspection |
| Main service water line replacement | Quoted after inspection |
| Drain or sewer line partial repipe | Quoted after inspection |
What moves the price: crawl space versus slab, how many fixtures the new lines feed, how many walls have to be opened, and the length of the main line. Every price is flat rate, so the number we quote is the number you pay.
How it works
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Call us
Tell us what you're seeing: rusty water, low pressure or leaks that keep coming back.
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We inspect
We look at the pipe from the crawl space or wherever we can reach it, check your pressure and tell you what's worth replacing.
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You get one price
A written scope and a flat price, whether that's one bad section or the whole house.
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We repipe and test
Old pipe out, new pipe in, a pressure test, and a walkthrough of what we changed.
What our job records show
15 jobs
Replacing or running new pipe since November 2025.
Those range from one corroded galvanized nipple in Woodacre to a full main service water line in Petaluma and a partial building sewer repipe in Mill Valley.
Galvanized pipe rusts from the inside, which is why older Marin homes end up with low pressure and discolored water. Pipe lining is common in Southern California, but it generally isn't an option on Marin jobs, so we replace failing drain lines outright.
Who does the work
Glenn Lopes
Owner and C36 license holder. Started Big Island Plumbing in 2017 after five years as a carpenter and a six month UPC code course. Five years of carpentry means he knows what's behind your walls before anything gets cut open.
Recent repiping reviews
Read all our reviews on GoogleWhere we repipe homes
Mill Valley
San Anselmo
Larkspur
Woodacre
San Geronimo
Fairfax
Santa Rosa
Corte Madera
Ross
Tiburon
Sausalito
We also repipe homes in Greenbrae, Kentfield and the rest of Marin and southern Sonoma County. See all service areas
Questions we get asked
How do I know if I need a repipe?
The usual signs are rusty or discolored water, pressure that keeps dropping, and leaks that show up in different places. If your home still has galvanized pipe, it's worth having it looked at.
How much does repiping cost?
It depends on the size of the house, how many fixtures the lines feed and how easy the pipe is to reach. We inspect first and give you one flat price for the whole scope before any work starts.
Will you have to open up my walls?
Often not much. A lot of Marin homes have a crawl space, so we can replace pipe from underneath. Homes on a slab or with pipe buried in finished walls take more opening up, and we'll tell you where before we start.
Can you replace just part of the system?
Yes. Plenty of jobs are one bad section, a main service line or a single drain run. We'll tell you honestly whether a partial repipe is enough or whether you'll be back in a year.
Do you replace drain and sewer lines too?
Yes. We repipe water supply lines and drainage, including building sewer and lateral sections.
Are you licensed?
Yes. Big Island Plumbing holds California C36 plumbing contractor license #1090862. You can verify it on the Contractors State License Board site.
Related services
Thinking about a repipe? Call (415) 209-8142
We'll inspect, tell you what's worth replacing and give you one price.