Requirement G1 states that wholesome water must be supplied to:
any place where drinking water is drawn off.
any sink provided in any area where food is prepared.

It also requires that wholesome or softened wholesome water is supplied to:
any washbasin or bidet provided in or adjacent to a room containing a sanitary convenience.
any washbasin, bidet, fixed bath or shower in a bathroom.
One of the reasons for setting out where wholesome or softened wholesome water should be supplied to is to clarify where it is acceptable for alternative sources of water, such as greywater and rainwater, to be used. G1(2) sets out that such alternative sources of water can be supplied to a sanitary convenience fitted with a flushing device.