What is the fixture unit value for a 1 1/4 trap?

The fixture unit value is a standardized metric used to account for the demand on a plumbing system created by various types of fixtures. For a 1 1/4 inch trap, the fixture unit value is assigned based on typical use and flow characteristics associated with that size trap.

Generally, a 1 1/4 inch trap is commonly used for lavatories, sinks, and similar fixtures. According to the Massachusetts Plumbing Code, these fixtures are categorized in such a way that they typically contribute a value of 1 fixture unit. This value helps in calculating the overall load on the plumbing system and determining the required pipe sizes and drainage capacities.

Understanding fixture unit values is essential for proper plumbing design and ensuring the system can efficiently handle waste without overflow or backup. The value of 1 for a 1 1/4 inch trap aligns with industry standards and practical usage guidelines, reflecting what is typically expected in a residential or commercial setting.