A water Part G report for Building Regulations deals with the sanitation, hot water safety and water efficiency requirements. Under Building Regulations, it is mandatory to comply with Requirement G2 – Water Efficiency of Part G.
The requirement states that “Reasonable provision must be made by the installation of fittings and fixed appliances that use water efficiently for the prevention of undue consumption of water”. Under Requirement G2 newly erected dwellings or dwellings formed by a material change of use (e.g. office-to-resi conversion) must demonstrate that the average potable water consumption does exceed 125 litres/person/day.
However, Local Councils can set more onerous targets as part of their policies or planning conditions. Additionally, under the Code for Sustainable Homes the following consumptions should not be exceeded: