What is the minimum size of a residential water service pipe?

The minimum size of a residential water service pipe is 3/4 inch. This size is commonly specified in plumbing codes because it provides an adequate flow rate for typical residential needs, ensuring that sufficient water pressure and volume are available for everyday activities such as showering, cooking, and washing.

Choosing a pipe size that is too small can lead to inadequate water flow, especially if multiple fixtures are used simultaneously. The 3/4 inch measurement allows for a balance between adequate supply and manageable pressure losses within the system, accommodating the demands of modern plumbing fixtures effectively. Larger sizes may be used in specific scenarios, such as when high water demand is anticipated, but for most standard residential applications, 3/4 inch is considered the appropriate minimum size.