San Jose · Santa Clara County
Slab Leak Repair in San Jose, CA
Most San Jose homes are 1950s to 1970s ranch houses built on slabs with copper water lines in or under the concrete, and those lines are now at the age where pinhole leaks appear. Eichler homes add a second possibility: a leak in the radiant heating pipes embedded in the slab.
- Independent local pros
- Free referral, no obligation
- You approve the price before work starts
What is different about slab leak repair in San Jose?
The two kinds of leak are diagnosed differently. A domestic water leak shows on the water meter and usually as a warm or damp spot on the floor. A radiant heating leak shows as a boiler that keeps losing pressure or needs topping up, and it will not move the meter in the same way. Tell the plumber if your home has in-slab radiant heat so they test the right system.
For domestic lines, the choice is between a spot repair through the slab and rerouting the line overhead. In a home where the copper is sixty years old, a second leak usually follows the first, which is why many owners move to a reroute or a full repipe. Failed radiant systems are often abandoned and replaced with a different kind of heating instead of being repaired in the slab.
From the San Jose plumbing guide
Slab leaks
Copper lines that have spent sixty years in or under a slab develop pinhole leaks. Once one line has failed, the others are the same age, which is why rerouting or repiping is often discussed after a second leak.
What to check and ask before work starts in San Jose
- Tell the plumber whether the home has radiant floor heating
- Ask how the leak was located before any concrete is cut
- Ask for a spot repair price and a reroute or repipe price
- Verify the C-36 license and ask who pulls the city permit
Licensing and permits for slab leak repair in San Jose
Plumbing contractors in California are licensed by the Contractors State License Board under the C-36 classification. In San Jose, plumbing permits are issued by the Planning, Building and Code Enforcement department. Neighboring cities such as Santa Clara, Campbell and Milpitas issue their own permits.
Keystream Plumbing is a referral service. We do not perform plumbing work or hold a contractor license. The independent plumber you are connected with is responsible for licensing, permits and the work itself.
What the job usually involves
The steps are the same in San Jose as anywhere; the local conditions above change how each one is done.
- Confirm and locate
- Choose the repair
- Repair
- Test and restore
Slab Leak Repair questions from San Jose
How do I know if my Eichler's radiant heat is leaking?
Signs include a boiler pressure gauge that keeps dropping, an automatic fill valve that runs often, warm or damp patches of floor and higher gas bills. A pressure test of the heating loops confirms it.
Is it worth repairing one slab leak in an older San Jose home?
A first leak can be spot repaired. Because the rest of the copper is the same age, ask for a reroute or repipe price too, so you can compare the cost of one larger job with repeated repairs.
Sources
- Water supply and water quality, Santa Clara Valley Water District (Valley Water)
- Check a contractor license, California Contractors State License Board
Local information reviewed October 5, 2026. Rules and programs change; confirm details with the agency before you rely on them.
More plumbing help in San Jose
Slab Leak Repair in other cities
Ownership rules, soil, water and pipe materials make this a different job from one city to the next.
Related guides: Signs of a Hidden Water Leak (and How to Check).
Need slab leak repair in San Jose?
Call (833) 520-4758. Same-day service is often available; call to check timing.