What is the minimum distance from the side of a stud to the center of a 90-degree fitting?

The minimum distance from the side of a stud to the center of a 90-degree fitting is crucial for ensuring that the piping system is installed correctly and complies with code requirements. When fitting the 90-degree fittings into a sprinkler system, this distance is important to provide adequate space to avoid damage to the pipe during installation and to maintain proper clearance for any future modifications or adjustments to the system.

The specified distance of 1-3/8" is based on common industry practices and standards that ensure there is enough space to secure the pipe properly, prevent strain on the fittings, and facilitate efficient connection to other piping components. This measurement also aims to help maintain the integrity of the structure and the sprinkler system’s operational effectiveness by allowing seamless transitions without interference from the surrounding framing materials.

In this context, the other distance options either exceed or do not provide enough room for the proper installation of the fitting. Hence, 1-3/8" is recognized as the minimum acceptable standard in many local codes and regulations to achieve these objectives.