IPS (Iron Pipe Size)

Iron Pipe Size (IPS) is a standard for measuring the diameter of pipes, originally developed for cast iron and steel pipes but now applied to other materials as well. IPS indicates the nominal diameter of the pipe, which does not correspond exactly to the pipe’s outer or inner diameter but serves as a standard reference for compatibility with fittings, valves, and other plumbing components. IPS sizing is commonly used in both residential and commercial plumbing systems, particularly for metal pipes, PVC, and CPVC fittings. Understanding IPS is essential for selecting the right pipe sizes, ensuring compatibility across different components, and maintaining proper flow rates and pressure in plumbing installations.