What is the maximum number of drainage fixture units (dfu) for a building drain with a 2-inch diameter pipe at a slope of 1/4 inch?

To determine the maximum number of drainage fixture units (dfu) that can be accommodated by a building drain with a 2-inch diameter pipe, one must refer to plumbing code tables, such as the Uniform Plumbing Code or the International Plumbing Code. These codes outline the capacities for different sizes of drain pipes and their ability to handle drainage fixture units based on their diameter and slope.

For a 2-inch diameter pipe, when it is installed with a slope of 1/4 inch per foot, it typically has a maximum capacity of 26 dfu. This is because the combination of pipe diameter and slope affects the flow characteristics. A proper slope ensures that waste flows efficiently through the pipe without causing blockages, and the diameter determines how much of that waste can be handled at any given moment.

It's important to note that the capacity can vary based on local codes and specific installation conditions; however, for most standard applications following common plumbing code guidelines, the figure of 26 dfu aligns with what is established for a 2-inch diameter pipe.