Look at Vent-Axia web site.
They have their "system calculator" document which gives info on duct and
fan sizes etc.
One thing to be aware of is the huge reduction in performance you will get
using concertina-type hose rather than smooth duct.
It may be far easier to route, but, size for size, it adds far more
resistance to air flow.

Phil [/quote]


Phil,
Thanks for the advice about the ducting. I had a look at the Vent-Axia website and it's just what I'm looking for don't know why I didn't find this when googling???