Home Design Guides: Sustainability, Plumbing
In most plumbing setups, it takes a while for hot water to reach the hot tap when it's turned on. Cold water diverters recycle the cold water which would otherwise pour down the drain in this time.
Water-producing bathroom fittings in Australia need to comply with basic water-efficiency standards. As a part of the WELS scheme, they are rated and given a label that shows how efficient they are.
See how lagging (insulation) and the distance that hot water has to travel through your pipes can affect energy efficiency in your hot water system.
Just because water from the tap has been used, it doesn't mean it can't be used again. See how grey water systems can help reduce your water waste.