In residential construction, what type of fixture shall not be individually valved?

In residential construction, a bathtub or shower is typically not individually valved to comply with plumbing codes and standards aimed at ensuring safety and functionality. The primary reason is that these fixtures are generally connected to a common plumbing system that allows for hot and cold water to mix before it reaches the fixture, making an individual valve unnecessary.

Having individual valves for bathtubs or showers can lead to complications such as water temperature fluctuations, especially if multiple fixtures are in use simultaneously. The design of plumbing systems often prioritizes the efficient use of space and reduces potential leak points by controlling flow at the source, which is often centrally located. By keeping the plumbing system simple and streamlined, the risk of failure or maintenance issues is minimized, thereby enhancing the overall reliability of the plumbing infrastructure in residential settings.

When considering the other fixtures mentioned, sinks, toilets, and dishwashers often require individual shut-off valves to allow for maintenance, repairs, or replacement without disrupting the entire plumbing system. This feature grants convenience and control to homeowners or service personnel, particularly for fixtures that may need more frequent servicing or could be isolated without affecting other water users in the home.