DIY polycarbide Greenhouse

Hello from Bradford,
BCEP is a local environmental charity and we are developing a community garden. We have limited funds to build a greenhouse and want to construct a wooden framed, polycarbide sheeted greenhouse.
 Does anyone have any tips or even better a design for such a structure.
 We are aiming for something around 4.2m wide and 8.5m long, 2.2 head room.

All advice grartefully recieved.
 Regards
 Carlton :blink:

use a local timber merchant for the timber it will work out a lot cheaper than b&q, especially if you ask them whats going to be cheapest, they may have some odd sized stuff available going cheap, especially if you go for random lengths, as they you get a mix of longer and shorter stuff (just remember to add 10% for wasteage)
if you arent fussy and tell them its for a community project they might even give a good discount.
Grendel

I made basically a cube the dimensions of corrogated roofing plastic. My mate made the wooden frame for me and I did the rest. You end up with a draughty box but it does the job. I've used old metal shelves inside and a defunct mini greenhouse. I made a wide shelf at one end to use for potting.
I anchored it by screwing it to some big treated timber lengths. They were attached to 4 stakes driven in to metpost things. (This was after it flew away from its first location.)
It is very useful although hellish hot in the summer. I usually take everything out in the summer and stand stuff outside on pallets.
When it rains it's great for sitting inside and drinking tea.

Have a chat with local window companies 1've just gained three UPVC framed double glazed windows that they have taken out and replaced with new ones that I'm going to use for cold frames then my plan is to aquire enought to build a greenhouse on the side of the shed.