rainwater harvesting for loo flushing

[Ali Twigg]

Hello people

I am interested in any information any of you have regarding a rainwater-flushing loo.

I have a flat garage roof and my bathroom backs onto said garage so there is a possibility of a collection tank being sited up their next to the loo. I thought this would reduce the need to pump the water to the cistern (if that's where it would go on such a loo) since there would be just the wall between the loo and the tank.

Also, being in an end terrace house we collect much of the run off from the other houses (4) in our row, ensuring a pretty good supply of rain water. As it's only going to flush the kazi I can't see the point of using drinking-quality water.

Does anybody know of a compatible or adaptable system in existence? Who knows, as all the houses on my side of the road have the same build design, we could start a fashion!

Please e-mail any relevant suggestions, links etc to a.twigg@hotmail.co.uk

Thanking y'all in anticipation

Ali Twigg

[SBromwich]

Being fairly new to rainwater harvesting I have looked at alot of systems before chosing the freerain system, so this is not expert advise but it may help.

There are a number of things to consider;

1. Gravity feeding the cistern will probably mean it takes an age to fill (depends on the pressure you can get) - I get 4 bar from the freerain pump which is like main pressure (great)
2. What happens if you run out of rainwater? (you still need to flush so you need to be able to get water from another source - namely the mains) -  But be careful here you can't connect between the two as you really need an air gap
3. You need to work out how much you need to store - the WC is about 25% of your water usage - find out your annual rain fall and then what roof area you are collecting from.  You also need to know what material the roof is made from.

Good luck.

Steve