In a plastic system, what is the minimum allowable pipe size?

The minimum allowable pipe size for a plastic system is typically ¾ inch. This size is often chosen to ensure adequate flow rates and to accommodate varying system designs while minimizing the risk of clogs or pressure loss. Smaller pipe sizes, such as ½ inch, may not provide sufficient volume or pressure, which can lead to performance issues in the system, particularly in larger installations or those with multiple outlets. Therefore, ¾ inch serves as a reliable compromise between flow capacity and system practicality, making it a standard minimum size for effective operation in various applications.