The water efficiency calculator for new dwellings
Details of the water calculation methodology for assessing the ‘whole-house’ water efficiency of new dwellings now up in our guidance section.
This document sets out the water calculation methodology for assessing the ‘whole-house’ water efficiency of new dwellings. The water calculator tool (Excel spreadsheet) is also available here
The calculation method is to be used to assess compliance against the water performance targets in building regulations 17 K. The code for sustainable homes now uses this calculator as the assessment methodology for WAT1.