What is the maximum weir height from a fixture outlet to a trap?

The maximum weir height from a fixture outlet to a trap is set at 24 inches. This measurement is crucial for ensuring proper drainage and preventing potential siphoning or backflow issues. When the weir height is kept within this limit, it helps maintain a consistent water seal within the trap, which is essential for blocking sewer gases from entering the living space.

Maintaining a maximum height of 24 inches helps ensure that the waste can flow efficiently into the drain system without creating excessive pressure or causing slow drainage. If the height were to exceed this measurement, it could lead to problems with drainage performance, including the risk of water seal loss in the trap, which could allow harmful odors or gases to escape.

In plumbing codes and guidelines, these parameters are established to promote safe and reliable plumbing systems. This information is designed to protect both the integrity of the plumbing installation and the health and safety of the occupants in a building.