Water Calculations (Part G)

MSAFE - Energy Assessments

Calculating your consumption of water

Part G of the Building Regulations require a water efficiency calculation to be carried out for all new dwellings. The calculation is to show the potential consumption of wholesome water per person per day. The calculations are based on fixtures & fittings in a dwelling and also any grey water or rainwater harvesting technologies that may have been utilised. Each dwelling is required to have a maximum consumption of 125 litres per person per day (l/p/day). 

Your development may even be required to achieve lower usage if built under The Code for Sustainable Homes:

  • Levels 3 & 4 ≤105l/p/day
  • Levels 5 & 6 ≤80l/p/day

MSAFE carry out all Water Calculations in accordance with the Government’s national calculation methodology - The Water Efficiency Calculator for new dwellings.

Contact MSAFE

Health and safety specialists MSAFE undertake work nationwide from our head office in Bournemouth acting as Energy Assessment and EPC advisors covering Dorset, Hampshire, Wiltshire, Bristol, Cardiff, Swansea, Devon, Cornwall, Gloucestershire, Oxfordshire and London.

To arrange a competitive fee proposal, please contact us on 0333 8000 700 or complete our enquiry form and we will contact you to discuss further.


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