This publication was withdrawn on
An updated water efficiency methodology is now included in Approved Document G. However, there will be cases where the previous document is still relevant (eg for development started before 1 October 2015).
The water calculator Excel spreadsheet has been removed due to technical problems. Free-to-download alternatives are available on the Internet.
Details of the water calculation methodology for assessing the 'whole-house' water efficiency of new dwellings.