Part G Water Efficiency Calculations

All new residential properties – whether newly built or converted - must now meet specific water efficiency targets by law. Under Part G of the Building Regulations, a maximum water useage figure of 125L per person per day must be achieved. As of 1st October 2010, non-compliance may adversely affect a dwelling’s SAP rating, and therefore its EPC rating.

The Code for Sustainable Homes (CSH) also imposes targets related to water usage, with generally more stringent requirements (for example, 80L at Levels 5 and 6).

Stroma carries out the water efficiency calculations required for new dwellings to comply with Part G and CSH. Calculations must be submitted at both the design and ‘as built’ stages; if your specification is not on target to meet the required limits, our assessors can advise on how to resolve this, ensuring a smooth submission to Building Control.

For help with meeting Part G or achieving your target CSH rating, please call us on 0845 621 22 22 or alternatively email This e-mail address is being protected from spambots. You need JavaScript enabled to view it .