I wanted to repair a dripping in-shower valve, and as the first step searched for a shut-off valve to the shower, only to discover there is apparently none. Similarly, I cannot find a valve for the second bathroom's tub supply only. All other fixtures have their shutoff valves.
My unit is a condo in a 3-story building located in the Los Angeles county, California. According to the LA county FAQ, state and county plumbing codes are based on the 2000 Uniform Plumbing Code, and the latter, if I am understanding it correctly (version on the Watt's site, PDF, page 29), seems to require that all fixtures could be shut off without shutting off other units:
605.3 In multi-dwelling units, one (1) or more shutoff valves shall be provided in each dwelling unit so that the water supply to any plumbing fixture or group of fixtures in that dwelling unit can be shut off without stopping water supply to fixtures in other dwelling units. These valves shall be accessible in the dwelling unit that they control.
The building was built around 1985. Hot water is heated centrally in the building, so I am looking for a pair of valves, not a small setup to overlook easily. How likely it is there is no such valve installed for the showers/tubs? What could be a less obvious location for the valve (inside the wall is very unlikely, is it?). It would not be a very big deal to arrange a time to shut off water with the neighbors, and the valves that shut off 3 units on one floor each are accessible with a step ladder in the underground garage, but I would avoid that if possible.
