Australia National Construction Code 2022 Volume Two (Building Code of Australia, Class 1 and 10 Buildings) WA-H9: Western Australia: WA Part H9 water use (WA H9P1 to H9P3)

For Class 1 buildings, associated Class 10a buildings and pools associated with a Class 1 building, WA H9P1 requires features that support efficient use of potable water, WA H9P2 features that prevent excessive loss of potable water (including from water holding structures) and WA H9P3 features that support efficient use of heated water, each appropriate to location, available supply and use. Deemed-to-Satisfy route: tap fittings (other than bath outlets and garden taps) of at least 4 stars WELS, showerheads of at least 3 stars WELS and dual-flush sanitary flushing of at least 4 stars WELS (WA H9D2); an outdoor private pool or spa supplied with a cover or blanket designed to reduce evaporation and, since Amendment 1 (1 May 2025), complying with AS 5348 (WA H9D3); and every internal heated water outlet connected to a heated or recirculating heated water system with pipes installed and insulated to AS/NZS 3500.4, the pipe to the furthest outlet not over 20 m long or 2 litres internal volume (WA H9D4).