What is the minimum height for a sink trap arm above the floor?

The minimum height for a sink trap arm above the floor is 2 inches. This requirement ensures that the trap arm is positioned adequately to prevent issues with drainage and ensure proper function. The height helps maintain the necessary slope for the waste water to flow effectively toward the drainage system while avoiding potential blockages or backflow.

A 2-inch elevation also helps in accommodating variations in floor height or any installed materials underneath, such as insulation or storage. Such considerations are essential for plumbing systems to work efficiently and prevent issues like siphoning or improper drainage. Maintaining this height is crucial not only for the functionality of the plumbing system but also for compliance with building codes and standards designed to ensure safety and efficiency in plumbing installations.