Recommended Sizes of Water Supply Lines

Sizing water supply pipes

Water supply pipe lines should be sized according expected demand and not the total theoretical demand from all fixtures at the same time. Due to the intermittent use of the fixtures it may be difficult to predict a realistic demand. 

The values below are relevant for supply lines to common systems like homes, offices, nursing homes etc.

Copper Pipe Size Total Maximum Theoretical Demand Summarized
(liter/s)
Maximum Expected Demand
(liter/s)
DN
(mm)
12 0.2 0.2
15 0.8 0.4
18 1.6 0.5
22 4.0 0.6
28 15 1.1
35 30 1.8
42 65 2.8
54 130 4.5

Search the Engineering ToolBox

Engineering ToolBox - SketchUp Edition - Online 3D modeling!

3D Engineering ToolBox - draw and model technical applications

Engineering ToolBox - SketchUp Edition - enabled for use with the amazing, fun and free Google SketchUp

Translate the Engineering ToolBox
About the EngineeringToolbox