Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

Hot and Cold Water Pipes Sizing

Recommended dimensions hot and cold water pipes.

The table below can be used to determine the maximum numbers of draw offs served by a pipe:

Hot and Cold Water Pipes Sizing
Nominal bore of pipeMaximum number of draw offs served
Flow pipesReturn pipes
inSteel pipe
(mm)
Copper pipe
(mm)
Head up to
20 m
(70 ft)
Head over
20 m
(70 ft)
1/2 15 15 1 1 - 2 1 - 8
3/4 20 22 2 - 4 3 - 9 9 - 29
1 25 28 5 - 8 10 - 19 30 - 66
1 1/4 32 35 9 - 24 20 - 49 67 - 169
1 1/2 40 42 25 - 49 50 - 79 170 - 350
2 50 54 50 - 99 80 - 153
2 1/2 65 67 100 - 200 154 - 300
  • Basins, sinks, showers and similar are regarded as 1 draw off
  • Baths and similar are regarded as 2 draw offs
3D Engineering ToolBox - draw and model technical applications! 2D Engineering ToolBox - create and share online diagram drawing templates! Engineering ToolBox Apps - mobile online and offline engineering applications!

Unit Converter


















































6.6.11

.