California · 21 covered places · 35 ZIP codes
Plumbers in San Mateo County, CA
We cover 21 cities and towns in San Mateo County, California, across 35 ZIP codes, including San Mateo, Daly City, Redwood City. About 716,000 people live in those ZIP codes. 41% of the homes were built before 1960, so galvanized pipe and old cast iron drains are common.
| Year built | Share of homes |
|---|---|
| Before 1940 | 9% |
| 1940–1959 | 32% |
| 1960–1979 | 33% |
| 1980–1999 | 16% |
| 2000 or later | 11% |
Share of housing units in the covered ZIP codes. Census ACS 2023 5-year estimates.
What goes wrong in San Mateo County homes
Pre-1960 homes: galvanized pipe and cast iron
41% of homes in San Mateo County's covered ZIP codes were built before 1960. Houses that old often still have galvanized steel supply lines that rust closed from the inside, and cast iron or clay sewer pipe that cracks and lets roots in. Weak pressure at upstairs fixtures, brown water after a shutoff and slow drains are the usual clues. Typical fixes are whole-house repiping and a sewer camera inspection.
1960s and 70s homes reaching end of life
33% of the housing here dates from 1960 to 1979. Original copper supply lines in those homes are now 45 to 65 years old, and cast iron drains of that age scale up inside and crack. Seized shutoff valves, pinhole leaks and recurring main-line clogs are common calls. A camera inspection shows the condition of the sewer line before anyone digs.
Natural gas in most homes
64% of occupied homes here heat with utility gas, so gas water heaters, ranges and dryers are common. That means gas line extensions for new appliances, flexible connector replacements and venting checks when a water heater is swapped. If you smell gas, leave first and call the gas utility from outside. See gas line repair.
Common plumbing work in San Mateo County
City pages in San Mateo County
Other covered towns in San Mateo County
- Atherton (1 ZIP)
- Belmont (1 ZIP)
- Brisbane (1 ZIP)
- Burlingame (2 ZIPs)
- El Granada (1 ZIP)
- Half Moon Bay (1 ZIP)
- La Honda (1 ZIP)
- Loma Mar (1 ZIP)
- Menlo Park (2 ZIPs)
- Millbrae (1 ZIP)
- Montara (1 ZIP)
- Moss Beach (1 ZIP)
- Pacifica (1 ZIP)
- Pescadero (1 ZIP)
- Portola Valley (1 ZIP)
- Redwood City (5 ZIPs)
- San Bruno (1 ZIP)
- San Carlos (1 ZIP)
- South San Francisco (2 ZIPs)
San Mateo County plumbing FAQ
Which towns in San Mateo County do you cover?
21 places: Atherton, Belmont, Brisbane, Burlingame, Daly City, El Granada, Half Moon Bay, La Honda, Loma Mar, Menlo Park, Millbrae, Montara, Moss Beach, Pacifica, Pescadero, Portola Valley, Redwood City, San Bruno, San Carlos, San Mateo, South San Francisco. Enter your ZIP code to confirm coverage for your street.
How old are homes in San Mateo County?
Across the covered ZIP codes, Census estimates put 41% of homes as built before 1960, 33% from 1960 to 1979, 16% from 1980 to 1999 and 11% in 2000 or later.
Who licenses plumbers in San Mateo County, CA?
The Contractors State License Board (CSLB) licenses plumbing contractors under the C-36 classification, and its online lookup shows license status.
Housing and heating figures are US Census Bureau ACS 2023 5-year estimates for the ZIP code areas we cover in San Mateo County, combined across places and weighted by housing units. Some ZIP codes extend into neighboring counties.
Need a plumber in San Mateo County?
Same-day service when a plumber is available. One call connects you with a licensed plumber who serves your ZIP.