"John" wrote in message
...
Toby gave a good response. Bear in mind that houses get sold - would
anyone
want to buy a house with some of the weird bodges suggested?

Well done Toby.

There are off the shelf greywater re-cycling systems around. In the BENELUX
countries it is standard in new builds to have a large tank under the ground
to collect rainwater from the roof.

There are a few packaged waste water units, I recall they are mostly
German. There is an American shower waste that is copper with a spiral of
pipe around the outside. The waster shower water spirals around the outside
of the waste pipe and passes heat to the incoming cold shower water in
effect it extends your cylinder size with making it larger.
http://www.endlessshower.com/ This unit really works. If you are clever
enough you can spiral soft copper around a large copper pipes and solder it
up.

It is effective as the hot shower waste water is dumped at the same time as
you are inputting cold water. You can dump a bath full of water and if no
one is using incoming water then it is wasted, unless it is stored in an
insulated tank.

Also concentrating on using less water, when on a meter, is very wise. We
spend as much on water as on gas, yet we all go ape about gas boiler/system
efficiencies and forget the water bills. Most water appliances, electrical,
toilets, basins (do you really need a large wash basin?) , etc can be low
usage. Power showers do not have to be 15 litres/min, 10 and less will do
as the power force of the water against the skin is what people want not so
much the volume. Environmentalist are lobbying ministers to restrict power
showers. Also restrict water volume into basins and the likes, where high
flows means more goes down the drain.