On Wed, 3 May 2006 13:51:07 +0100, "Rupert \(W.Yorkshire\)"
wrote:


"chris French" wrote in message
k...
In message , KK
writes
Hello, - there have been several posts about water butts recently.

How big does it need to be

Depends on how much you want to consume. In general I'd say the
bigger/more of them the better.

& what if it overflows ?

Are they easy to plumb in to the downpipe ?

If you use the special diverters you can get for downpipes, then once it
is full it doesn't fill up anymore and the water just goes straight down
the downpipe.
--
Chris French

Chris how does that work? Does it have some kind of float valve. I have only
ever used the original models which had a separate overflow back into the
downpipe.

They work because when water flows in the downpipe, surface tension
ensures it flows over the inner surface, not as a stream down the
centre of the void, IYSWIM. The diverter has a shallow annular
'gutter' arrangement on the inside, which intercepts this surface flow
and diverts it off into the butt. When the butt is full, the water
backs up the connecting pipe and overflows the shallow internal
'gutter' and then on down the downpipe.

For the system to work properly, the diverter on the downpipe _must_
be at _exactly_ the same level as the surface of the water in the butt
when the latter is full. The easiest way to get it right is to fit the
diverter in the downpipe fractionally too high (say an inch or so, but
no more) and then raise the level of the butt with packing such as
concrete slabs, old slates etc. to get the level just right.

For the OP, I would choose the biggest butt you can get or that will
fit the space available. If you can, get several butts and link them
together as near to the bottom as you can (butt suppliers do linking
kits). Linking them in that way means they all fill to the same level
and you only need one outlet tap.

Inlet =| | | | | |= Alternative inlet
|butt1| |butt2| |butt3|
| | | | | |
|_____|====|_____|====|_____|=Tap
link link

I find it's amazing how rapidly the levels drop when you are watering
a lot. I have two butts linked as above, and they're only two thirds
full ATM, and it's only the beginning of May. We only had half our
average rainfall last month :-(




--
Chris

E-mail: christopher[dot]hogg[at]virgin[dot]net