What have I done?

[bobleponge]

The boss doesnt know yet but I think I have just bought the frame of a polytunnel for a ridiculously small amount of euro's.
Has anyone ever bought just a frame and then fitted a sheet?
Are there any links, articles on just such a foolish escapade?
HELP.
I vaguely remember reading in another magazine and the bloke dug trenches down the sides for the plastic?? maybe?? Cant quite remember.
I wasnt intending to buy one just yet, but was so cheap I couldnt refuse.
Now I need tips,help,advice or confirmation of sanity.

[terrier]

If we wer'nt all insane, we probably would'nt try GYO. If you lived closer I'd come round and make you an offer for it If you really want to worry 'the boss', tell her its part of the roof for a Dutch Barn you're building

[Janco]

I had a polytunnel for several years and you can buy the covers separately but you'll need to know the size. You really need 4 people available to fit a cover and warm weather. We fitted ours on a cold day with only 2 of us and it never fitted as well as it should have done but what we grew inside was great. The wind was a bit of a problem on our exposed site and even though we dug trenches all round the cover still escaped in places. I now have a heavy duty greenhouse that replaced the polytunnel and use the frame of the polytunnel as a fruit cage covered with netting and I am really pleased with that.

[pigletwillie]

I have now build two homemade tunnels and I mean proper jobbies. They are 20 x 10 by about 9' high. Here are some pictures of the finished article.

To secure the plastic I surrounded the base with scaffolding planks but 6 x 2 would do just as well, this was well secured and the plastic was attached to it. It is much better than trenching as you can tension more and it doesnt pull out like trenching can, especially after lots of rain.

Many tunnel manufacturers will sell you the plastic and all have calculators on their websites for you to get the correct size of sheet.

[sewer rat]

Re confirmation of sanity - nothing surer than your sanity - you've just invested in a tunnel !!
Re plastic coverings. As PW says, measure you tunnel, length, breadth and height at tallest point, then phone some of the polytunnel companies and get prices - they will tell you what size of sheet you need. Don't forget door sizes as some companies will sell these seperately. Also, might be worth looking at some tunnel sites on-line as there are a fairly wide variety of covers available, including thermal anti fog which allegedly stops or at least cuts down condensation dripping onto your plants - it beads then runs down the internal wall of the tunnel.
Good luck

[Matt.]

So how do you secure to scafolding boards? Do you sandwich between two planks? How do you stop any holes making a weak point - do you use eyelets? I don't have a poly tunnel or intend on getting one but its the only stage of your (or somebody elses DIY) guide I didn't get.

[pigletwillie]

The boards are bolted to the uprights using u bolts. The plastic is then sandwiched between the board and a piece of 6 x 1 which are then screwed together. There are no holes and no eyelets.

[Matt.]

Ok so its as I thought. When you screw the 6x1 to the scaffolding this must go through the plastic. I thought this would make a weak point but I suppose it depends how tight you can make the clamp. Either way its much tougher than burying the excess under soil and a great idea.