In plumbing, what does DFU stand for?

DFU stands for Drainage Fixture Unit. This term is used in plumbing to quantify the load on a drainage system from various plumbing fixtures. Each type of fixture has a designated DFU value based on its average usage and drainage characteristics. This standardization allows plumbers and engineers to calculate the required size for pipes and drains, ensuring that the system can adequately handle the wastewater flow during peak usage times.

Understanding DFUs is crucial for designing effective plumbing systems. By using these units, professionals can determine the necessary slope, size, and layout of drainage pipes to avoid issues such as clogs and backups. This concept is fundamental in plumbing engineering and codes, such as the International Plumbing Code (IPC) and the Uniform Plumbing Code (UPC), which provide guidelines on how to implement DFUs in system design properly.