Potable Water Consumption in new Dwellings

The requirement to limit the consumption of potable water in dwellings is covered under both the Building Regulations and the Code for Sustainable Homes (The Code). There is now a unified calculation method of determining this consumption, produced by BRE Global Ltd on behalf of Communities and Local Government

Thermal Solutions can provide calculations and guidance to support the proposed appliances of a new home, or recommend a set of performance standards that the appliances need to achieve.

The calculation procedure ultimately involves the use of test data from the appliances' manufacturers - it does not give a "real" consumption, as this will be affected by local water pressure and the pattern of use by the home owners

Certain appliances are exempt from these calculations, these include Bidet's, Jacuzzis and swimming pools - although The Code can account for these in other parts of its' system. A standard assumption of  5 litres per person per day is made to allow for external taps for garden irrigation.

The calculations take into account

  • Taps - litres per minute flow rate

  • Showers - litres per minute flow rate

  • WC's - flushing capacity in litres

  • Baths - total capacity of bath to overflow in litres (the taps on baths are ignored)

  • Dishwashers - Litres per place setting

  • Washing machines - litres per kg of dry load

  • Waste disposal - where present, a standard assumption is made

  • Water softener's - water is consumed during cleaning of the filters

  • Water harvesting - from rain or certain internal appliances

If you would like to discuss your project or would like a quotation, go to the Contact Us page for details on how to proceed.