If the cold water supply fixture unit demand increases to 51 cwsfu, what size should the cold water main be increased to?

When determining the appropriate size for a cold water main based on the cold water supply fixture unit demand, it's important to reference the plumbing code or guidelines that dictate how to size water piping based on various flow demands.

In this case, the demand has increased to 51 cold water supply fixture units (cwsfu). Typically, plumbing codes provide charts or tables that correlate fixture unit demands with the corresponding pipe sizes needed to maintain adequate flow and pressure.

For a demand of 51 cwsfu, a 1-1/4 inch pipe is typically needed to ensure that the system can adequately handle the flow without excessive pressure drop or water hammer that can occur with undersized piping. This size would generally provide sufficient flow capacity for the fixture unit demand indicated, minimizing any potential issues related to inadequate supply during peak usage times.

In contrast, a size of 1 inch may not be sufficient to handle 51 cwsfu, leading to lower water pressure and potential service issues. A 1-1/2 inch pipe could handle the demand as well, but it may be oversized based on the specific calculations or tables provided in the applicable plumbing code. The 2 inch size, while certainly adequate, would be unnecessarily large for this demand,