What is the maximum vertical distance from the outlet of the fixture to the trap weir?

The maximum vertical distance from the outlet of the fixture to the trap weir is specified as 24 inches to ensure proper drainage and prevent issues such as siphoning or incorrect trap function. This distance is critical because if the vertical distance exceeds this limit, it may lead to problems with wastewater flow, contributing to clogs or failures in the drainage system. A properly functioning trap is essential for creating a seal against sewer gases while allowing waste to flow freely. Staying within this measurement helps maintain the trap’s effectiveness and overall plumbing system reliability.