Flow Rate Charts

Tables, charts, diagrams, templates, and other design help is available from this page.

Flow Rate Charts

Pipe SizeMaterialFlow Rate Min/Max
3/8&Prime Copper 1.0 2.0
1/2&Prime Copper 1.6 3.2
3/4&Prime Copper 3.2 6.5
1&Prime Copper 5.5 10.9
1 1/4&Prime Copper 8.2 16.3
1 1/2&Prime Copper 11.4 22.9
2&Prime Copper 19.8 39.6
2 1/2&Prime Copper 30.5 61.1
3&Prime Copper 43.6 87.1
Pipe SizeMaterialFlow Rate Min/Max
3/8&Prime PEX 0.6 1.3
1/2&Prime PEX 1.2 2.3
5/8&Prime PEX 1.7 3.3
3/4&Prime PEX 2.3 4.6
1&Prime PEX 3.8 7.5
1 1/4&Prime PEX 5.6 11.2
1 1/2&Prime PEX 7.8 15.6
2&Prime PEX 13.4 26.8
Pipe SizeMaterialFlow Rate Min/Max
3/8&Prime PEX-AL-PEX 0.6 1.2
1/2&Prime PEX-AL-PEX 1.2 2.5
5/8&Prime PEX-AL-PEX 2 4
3/4&Prime PEX-AL-PEX 3.2 6.4
1&Prime PEX-AL-PEX 5.2 10.4

Flow Rate Min is based on a minimum velocity of 2ft/sec, and Flow Rate Max is 4ft/sec. More on the effects of lower or higher flow rates.