I have a problem. Hope someone comes up with a solution to this. This is a problem I believe in all the homes in USA. You turn the tap left for hot water and right for old water. Have you ever noticed when you open up a tap and if the water is not at the right temperature you let the tap running until you get the right temperature. Imagine how much water we are wasting in this. There are workaround you can do at the personal level but ideally tap system needs to be changed this fix this issue. Oh one more - for those who have bad habits of keeping the tap running when they don't need it, the home tap system can have a built in motion sensor like you find in public places to stop the wastage.

The simplest/cheapest solution for this is to use a point-of-use (POU) heater at the sink. These can be with or without a tank. For hand washing application a tank-less POU heater will work. They can heat water with about 1.5gpm of flow - plenty for hand-washing . Typically they cost arount $170 - $230.