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Low Water Pressure in San Francisco, California 94102
The typical home here dates from 1943, which predicts the supply pipe. Whole house or one tap, and who to call.
Free to homeowners in San Francisco — the contractor pays us for the introduction, you never do.
The short answer
The median home in San Francisco dates from 1943, which puts galvanized steel supply pipe in the frame: it loses bore from the inside and loses it everywhere at once. Weak pressure at every tap points at the supply, while one weak tap usually points at that fixture.
Source: US Census Bureau, American Community Survey 5-year estimates, table B25035.
San Francisco has 361,770 occupied homes across 26 ZIP codes. Across all its housing, vacant units included, the median build year is 1943 — the most useful single fact for working out why the water pressure is weak, because it predicts what the supply pipe is made of.
What this site is
PressureTrace is a referral service, not a plumbing contractor. We connect homeowners with independent contractors. Contractors are required to hold whatever credential their state or municipality demands. Every state page sets out who licenses plumbers there and where to check, so you can confirm before work begins. We do not perform plumbing work, we do not set prices, and we never charge homeowners anything — the contractors in our network pay us when we route them a call.San Francisco sits 28 years older than the CA median of 1971. Of the 257 CA towns we route calls in, its housing is older than 99% of them, and by number of homes it ranks 2nd.
What 1943 tells you about the pipe in San Francisco
Housing of this vintage generally means galvanized steel as standard, and at this age the inside diameter of a half-inch line can be materially narrower than it was when it was fitted. The classic sign is that pressure is worst at the fixtures furthest from where the water comes in. More on 1940s supply pipe.
39% of occupied homes in San Francisco are owner-occupied, 14 points below the CA figure of 53%. It matters here because the run between the meter and the house belongs to the property owner, not the utility.
Median household income across San Francisco ZIP codes is $152,403, 46% above the CA median of $104,737.
Source: US Census Bureau, American Community Survey 5-year estimates, 2023 release — tables B25003 (occupied units), B25035 (all units) and B19013 (households). How these are aggregated.
In a town of this vintage the first question in San Francisco is still how many taps are weak, and the answer usually comes back "all of them" — which points at the supply rather than at any fixture. Normal is 45–80 psi, under 40 psi is low, and a gauge settles it in a minute. Whole house is worth a call; one tap is usually yours to fix.
Build year and occupied homes by ZIP code in San Francisco
| ZIP | Typical build year | Occupied homes |
|---|---|---|
| 94102 | 1941 | 19,543 |
| 94103 | 1992 | 17,352 |
| 94105 | 2008 | 8,316 |
| 94107 | 1998 | 15,761 |
| 94108 | 1939 or earlier | 6,326 |
| 94109 | 1939 or earlier | 31,899 |
| 94110 | 1939 or earlier | 26,984 |
| 94111 | 1978 | 2,471 |
| 94112 | 1940 | 23,274 |
| 94114 | 1939 or earlier | 16,804 |
| 94115 | 1949 | 16,725 |
| 94116 | 1944 | 15,355 |
| 94117 | 1939 or earlier | 17,558 |
| 94118 | 1939 or earlier | 16,995 |
| 94121 | 1939 or earlier | 18,175 |
| 94122 | 1943 | 22,375 |
| 94123 | 1939 or earlier | 12,510 |
| 94124 | 1966 | 10,982 |
| 94127 | 1939 or earlier | 7,466 |
| 94129 | 1951 | 1,338 |
| 94131 | 1962 | 12,469 |
| 94132 | 1951 | 10,686 |
| 94133 | 1939 or earlier | 12,954 |
| 94134 | 1953 | 12,545 |
| 94158 | 2009 | 4,907 |
Nearby towns we cover
- Burlingame typical build 1959 · 16 years newer
- Daly City typical build 1965 · 22 years newer
- Millbrae typical build 1960 · 17 years newer
- Pacifica typical build 1966 · 23 years newer
- San Bruno typical build 1961 · 18 years newer
- South San Francisco typical build 1963 · 20 years newer
Worth reading for a 1943-era home
- galvanized supply pipe
- whole-house pressure loss
- pressure worse upstairs
- how to test your pressure
- low pressure on hot only
ZIP codes we route in San Francisco
- 94102
- 94103
- 94105
- 94107
- 94108
- 94109
- 94110
- 94111
- 94112
- 94114
- 94115
- 94116
- 94117
- 94118
- 94121
- 94122
- 94123
- 94124
- 94127
- 94128
- 94129
- 94131
- 94132
- 94133
- 94134
- 94158
Low water pressure help near me in San Francisco
Have the San Francisco ZIP code ready and say what the taps are doing. We route it to an independent contractor who covers that area. We are not the contractor, we do none of the work, and you are never charged for the call or the referral. We are named for pressure and not limited to it.
Low Water Pressure coverage in San Francisco, CA
San Francisco spans San Francisco and San Mateo Counties, California. It covers 51 ZIP codes: 94102, 94103, 94104, 94105, 94107, 94108, 94109, 94110, 94111, 94112, 94114, 94115, 94116, 94117, 94118, 94119, 94120, 94121, 94122, 94123, 94124, 94125, 94126, 94127 and 27 more. We route low water pressure calls from every one of them.
What happens when you call
No form, no quote tool, no waiting for an email.
- You tell us what the water is doingOne short conversation. If it turns out to be something you can fix in five minutes, we will say so.
- We route the call in San FranciscoWe match 94102 to an independent contractor who already covers San Francisco — not a call center three states away.
- They quote, you decideWe do not set prices and we never charge you. The contractor pays us for the introduction.