The northern and central neighborhoods of San Francisco hold much of the city's Victorian and Edwardian housing: the flats of the Western Addition and the Haight, the grand houses of Pacific Heights, the long rows of the Richmond. Nearly all of it was built before cars and before modern water heating, and its heaters live in spaces that were adapted for them later.
Buildings and heater locations
Victorian and Edwardian flats. Two- and three-unit buildings from the 1880s through the 1910s, common in the Western Addition, the Haight, Cole Valley and the Inner Richmond. Heaters usually sit on the converted ground floor, one per flat, or in a basement below.
Large single-family houses. Pacific Heights and Presidio Heights homes often have genuine basements with utility rooms, sometimes with more than one heater serving a large house.
1920s and 1930s homes. The Marina, Cow Hollow and much of the Outer Richmond have homes with a street-level garage and the heater at the back.
Apartment buildings. Scattered throughout, with unit closets or central systems.
The Presidio. Historic and renovated residences with their own layouts, managed as a distinct area.
Converted ground floors and basements
When these buildings were adapted for cars and modern utilities, water heaters went wherever there was room on the lowest level: behind a garage, under a stair, in a corner of a basement with a low ceiling and exposed beams. That creates a few recurring conditions. Space is tight, and a replacement tank may not be the same shape as the old one. Walls are often brick, concrete or irregular framing. Vents may run long distances or join older flues. And the route in and out, past parked cars or down narrow stairs, needs planning.
None of that makes a replacement unusual here; it makes it a job for someone who does it regularly. The installer measures height, width and the path in, checks the vent and combustion air, and prices any adjustments before starting.
Fit, vent and route checked before a new unit is ordered.
Several heaters in one basement
Multi-flat buildings often have a heater per unit lined up in a shared space. They tend to be installed around the same time and fail around the same time, and they're not always labeled. When one fails, it's worth having the others checked, and labeling them properly saves confusion later. Owners of multi-unit buildings sometimes plan replacements for all the units together.
Securing heaters in old buildings
Seismic attention is heaviest in San Francisco, and these neighborhoods show why securing a heater takes thought. Brick and concrete basement walls need suitable anchors. Heaters standing away from a wall need other means of being held. Old gas lines and vents must tolerate a little movement, and a row of heaters means each one is secured. In and around San Francisco, requirements are set locally; the installer confirms what applies at your address. A heater secured differently from a neighbor's isn't necessarily a problem.
Venting in older buildings
Victorian and Edwardian buildings have usually been re-vented several times. A vent that was shared with a long-gone furnace, a connector that has sagged or corroded, or a closet enclosed during a remodel can all affect how a gas heater draws. On every replacement the installer checks draft, the vent's condition and the combustion air to the space. Where a vent change is needed, a direct-vent or power-vent unit sometimes offers a cleaner solution.
Cool, often soft water
Inlet water here is cool year-round and colder in winter, so heaters recover slowly and sizing for January matters. Many households have relatively soft water compared with inland California, so sediment builds more slowly, although anodes and relief valves still need periodic checks. In and around San Francisco, your water provider can tell you about your supply.
ZIP codes in this district
These are the ZIP codes this district page serves, from the Marina to the Outer Richmond.
ZIP codes served: 94115, 94117, 94118, 94121, 94123, 94129, 94143
Other San Francisco districts: Downtown, SoMa and North Beach, the Sunset and southwest and the Mission, Castro and southeast. Across the Golden Gate: Sausalito and Mill Valley. Back to all of San Francisco.
Relevant services
Same-age heaters in a shared basement often fail together.
Richmond, Haight and Pacific Heights questions
Very. Most of these buildings predate cars, and their ground floors were converted to garages and storage later. Water heaters moved down there too. Space is often tight and walls irregular, which affects fitting and securing a new heater, but it's a standard installation for the neighborhood.
It's common for multi-flat buildings to have a heater per unit lined up in a shared basement or garage, and they're not always labeled. A technician can trace which heater serves which flat and label them, which saves confusion the next time something goes wrong.
Usually, but it needs measuring. Newer tanks can be wider or taller because of added insulation, and basements and converted ground floors can have low ceilings, pipes and beams in the way. The installer checks height, width, the vent route and the path in before recommending a unit.
A low ceiling can rule out some tall tanks and many heat pump units, which also need more air around them. A shorter tank, a different capacity or a wall-mounted tankless unit may fit better. The installer can compare options for the space.
Older buildings often have vents that were shared with furnaces, rerouted during remodels, or are simply worn. A new heater needs a vent that suits it and draws properly, and a closet or basement needs adequate combustion air. If changes are needed, they belong in the quote.
Many Marina and Cow Hollow homes from the 1920s and 1930s have a garage at street level with the heater at the back, similar to the Sunset. They're generally more straightforward than a converted Victorian ground floor. Garages there are often tight around parked cars, so keeping clear space in front of the heater for service is worthwhile.
Masonry and concrete need anchors suited to them, and the installer checks the wall's condition first. Where the heater sits away from a solid wall, other ways of holding it firmly may be used. Requirements are set locally; the installer confirms what applies at your address.
Seven ZIP codes listed in the service-area section: Pacific Heights and the Western Addition, the Haight and Cole Valley, the Inner and Outer Richmond, the Marina and Cow Hollow, the Presidio, and the Parnassus Heights area. Sausalito and Mill Valley, across the Golden Gate, have their own pages.