What is the minimum size of a fixture water supply pipe for a single showerhead?

The minimum size of a fixture water supply pipe for a single showerhead is 1/2 inch. This size is sufficient to provide adequate water flow and pressure to ensure a good shower experience. Using a 1/2 inch pipe helps to avoid unnecessary restrictions in the water supply, which can lead to poor performance, such as low water pressure or inadequate flow rate. Adequate supply lines support the intended usage of the fixture, adhering to plumbing codes, which typically specify this size for individual fixtures like showerheads to ensure they operate effectively and efficiently.

Smaller pipe sizes, such as 1/4 inch, are generally insufficient for this application, as they cannot provide enough flow or pressure. Larger sizes, such as 3/4 inch and 1 inch, are usually reserved for main supply lines or multiple fixtures, as they can lead to an oversupply of water that might create issues like wasted water or increased costs without a corresponding benefit to the performance of a single showerhead.