Outside Diameter of PEX Tubing

PEX tubing is designed to replace copper with maximum ease. This is why PEX of any given size has the same outside diameter as copper of the same size. PEX's inside diameter, however, is smaller because PEX is thicker than copper. Any flow lost by the smaller inside diameter can be made up for by the fewer bends and elbows in PEX systems. PEX tubing is perfect for retrofit designs. It’s easy to run and can fit in tight spaces. PEX tubing and copper tubing with the same nominal size can fit into the same SharkBite fittings.