Leaks, pipes & freezing · San Jose
Leak detection in San Jose, CA
Turn off every fixture and watch the water meter's leak indicator. If it moves, water is leaking somewhere. A plumber uses pressure tests, acoustic listening and thermal imaging to find the leak so only a small section of wall or floor has to be opened.
- Licensed local plumbers
- The problem explained before work starts
- Price agreed before the job begins

Leak detection for San Jose homes
Hidden leaks waste water and rot framing before anyone sees them. In dry climates a slow leak can evaporate as fast as it drips, so a stain may never appear. The first sign is often a water bill that jumps between seasons that should match.
For the full guide, including what you can safely do before a plumber arrives, see leak detection explained.
Leak detection in San Jose at a glance
- Urgency
- Usually plannable
- Area
- San Jose, CA
- Who does the work
- An independent, licensed local plumber
- Permit
- Plumbing permits are issued by the City of San Jose's Building Division in Planning, Building and Code Enforcement.
- Typical steps
- Meter and isolation test → Pinpoint → Open and repair → Document
- Availability
- Call now to check plumber availability
Signs you need leak detection in San Jose
- A water bill higher than the same month last year
- The meter's small triangle or dial turning with everything off
- Warm spots on a floor (a hot water line leaking under a slab)
- Musty smells, bubbling paint or warped baseboards
- Constant sound of running water
Local conditions
Leak detection in San Jose: what's different
Copper lines under 1950s–70s slabs in Cambrian, Almaden Valley and Evergreen develop pinhole leaks after decades of hard water. Warm floors, the sound of water and a higher bill are the common signs, and a slow leak under the slab can run for months before anyone notices.
A plumber confirms the leak at the meter, then uses acoustic listening and thermal imaging to pinpoint it, so only a small section of floor is opened or the line can be rerouted through walls or the attic. Rerouting is often the better long-term fix when the rest of the copper is the same age.
- Water and sewer in San Jose
- Water service is split among San Jose Water (a private utility), San Jose Municipal Water and Great Oaks Water, depending on the address. The city provides sewer service.
- Permits in San Jose
- Plumbing permits are issued by the City of San Jose's Building Division in Planning, Building and Code Enforcement.
San Jose housing and plumbing
Willow Glen and Rose Garden homes often have galvanized supply and cast-iron or clay drains. The 1950s–70s tracts have copper supply now prone to pinhole leaks, often on slab foundations.
Neighborhoods and ZIP codes
Plumbers on Thawline cover San Jose and Santa Clara County, including Willow Glen, Rose Garden, Almaden Valley, Evergreen, Cambrian, Downtown. ZIP codes: 95101 · 95103 · 95106 · 95108 · 95109 · 95110.
Other San Jose conditions that affect plumbing
- Hard water: Hard water builds scale in water heaters and tankless units, shortening their life.
- Slab leaks in copper: Copper lines under 1950s–70s slabs develop pinhole leaks, often found by warm floors or high bills.
- Earthquake readiness: California requires water heaters to be strapped, and flexible gas connectors reduce break risk.
- Older Willow Glen drains: Willow Glen and Rose Garden homes often have clay sewer laterals and cast-iron drains, and mature trees send roots into the joints, causing repeat clogs.
How leak detection works in San Jose
- 1
Meter and isolation test
Fixtures are shut off one branch at a time to see which part of the system is losing water.
- 2
Pinpoint
Acoustic listening, thermal imaging and moisture meters narrow the leak to a small area.
- 3
Open and repair
Only the area over the leak is opened. Repairs are made and pressure tested.
- 4
Document
You get a written description of the cause for insurance or a future buyer.
What affects leak detection cost in San Jose
Every job is priced by the plumber after they see it. These are the things that move the price most. Ask for the price before work starts.
- Supply leak versus drain leak
- Leak location: wall, ceiling, under a slab or in the yard
- Equipment needed to pinpoint it
- Access and patching (drywall repair is often a separate trade)
Leak detection questions in San Jose
Should I reroute or repair a San Jose slab leak?
How do I check my meter for a leak?
Is the leak my responsibility or the water utility's?
Which homes get slab leaks?
Also in San Jose
Related
Related plumbing services

Burst pipe repair
Turn off the main water shutoff first, then open a faucet on the lowest floor to drain the lines.
Learn more
Water line repair
The water service line runs from the curb stop near the street to your house, buried below the frost line.
Learn more
Repiping
Repiping replaces a home's water supply lines, usually because old galvanized steel has corroded or polybutylene is at risk of failing.
Learn more
Toilet repair
A toilet that runs needs a new flapper or fill valve.
Learn moreGuides
Read before you call
Emergencies
What to do when a pipe bursts
Shut off the main water valve, open the lowest faucet in the house to drain the lines, turn off the water heater, and cut power to any room where water is reaching outlets. Then call a plumber, photograph the damage, and call your insurer.
Emergencies
How to find and test your main water shutoff
Look where the water line enters the house, usually through the basement or crawl space wall facing the street, next to the water meter. Test it once a year by closing it and confirming water stops at a faucet, so you know it works before a pipe bursts.
Costs & planning
High water bill? How to find a hidden leak
Turn off every fixture and watch the meter's leak indicator for 15 minutes. If it moves, put dye in each toilet tank, check the water heater and irrigation, then call for leak detection if you still can't find it.
Need leak detection in San Jose?
Tell us what's going on and your ZIP code. You'll be connected with a licensed plumber who serves your area.
Call now to check plumber availability
