When installed horizontally, PEX sizes 1-1/4" and larger shall be supported at intervals not to exceed how many inches?

When PEX piping sizes 1-1/4 inches and larger are installed horizontally, they must be supported at specific intervals to ensure proper alignment, prevent sagging, and maintain system integrity. The requirement for horizontal support intervals specifically states that such pipes should be supported at intervals not to exceed 48 inches. This is crucial for preventing excessive weight on joints and fittings, which can lead to leaks or failures over time.

Supporting PEX at the correct intervals is especially important because it is a flexible material, and without proper support, it can experience bending or stress that may compromise its performance. An interval of 48 inches provides a reliable framework to keep the pipe stable while accommodating any necessary expansion and contraction due to temperature changes.

Other potential choices reflect longer support distances that do not adhere to the guideline established for larger PEX sizes, which would increase the risk of installation problems. Therefore, adhering to the 48-inch support interval is essential for ensuring compliance with plumbing codes and maintaining the overall reliability of the plumbing system.