What is the maximum horizontal distance from the standpipe trap to the outlet of the laundry tray?

The maximum horizontal distance from the standpipe trap to the outlet of the laundry tray is established to ensure proper drainage and prevent issues such as siphoning, backflow, or incomplete drainage of wastewater. In this case, a distance of 30 inches is recognized as the standard maximum distance within the International Residential Code (IRC).

Maintaining this 30-inch limit is crucial because if the distance were any greater, it could compromise the system's ability to effectively remove wastewater. The closer proximity of the standpipe trap to the laundry tray allows for better gravitational drainage, which is essential for the system to function as intended without obstruction or delays in water flow.

Designing plumbing systems with these standards helps ensure safety, reliability, and compliance with code requirements, which ultimately benefits homeowners and reduces risks of future plumbing problems.