Sanitary installations must comply with local and national water supply regulations (Water Supply Regulations, Scottish Bylaws, NF P 41-205, REEF, DTU 60-11…) bylaws and plumbing regulations.
These are, however, often incomplete for installations fitted with time flow controls.
They require a particular assessment.
Pipework diameters are often chosen depending on the flow rate they provide to the different points-of-use, their development, the distribution height and the minimum static pressure available.