Had a quick look out the back, only fan we have on hand is a big 3 phase
one which would probably crush the shed like a coke can....
Could also try supagas/BOC as they do a lot of fume extraction stuff for
or Air Diffusion (off saints road at Salisbury), the have flexible duct,
transfer fans etc... or its been a while since I have been in a cash
converters, but they always seemed to have a 'hydro' section.