advice with polytunnel please

[Smooth Hound]

i am putting the frame of my 12 ft ish wide and 25 ft long polytunnel. my question, keeping in mind that it is second hand and i didnt see it up before , when you put your bars up, do you put the bars in the ground at the width it naturally becomes with no force,(in my case that would be 14 ft,) in which case my bars would have to go in the ground at a slight angle, or would i push it together a bit so it is under a bit of tension and put them in at 12.5/13ft apart, which would mean that the bars would go into the ground at 90 degrees, and would give me a suitable height as well, . When i say bars in the ground i men the anchor bars, not the actual greenhouse bars which would sit in the anchor bars. so if any one can remember as to whether they had to push the width together or not when putting theirs up, i would be grateful.

[Camile]

Hello,

when we've put ours up, the bars went into the ground vertically, but I believe that's because it's a straight high sided one ...

and the bars were under a bit of pression but not that much either ... it kind of fit well if you get my drift ..

are you sure it's not a 14ft x 25ft ?

in that case your problem is solved ...

and make sure the diagonals are right before driving the poles down .. as it's the most important ones to get right for stability and strength .. .

Good luck,
Camile

[maggienetball]

I find the book "Gardening under Plastic" by Bernard Salt invaluable for both erecting the tunnel and then planting all year in it. Shows you everything you need to know.

[camillitech]

Morning SH,

aye they're supposed to be under tension, If your interested A mate of mine is making one out of plastic pipe and I'm following it on my blog, also there's quite a bit about polytunnels on Thurston Gardens blog http://www.thurstongarden.wordpress.com/

Good luck, Paul

[Smooth Hound]

[quote="Camile"]Hello,

when we've put ours up, the bars went into the ground vertically, but I believe that's because it's a straight high sided one ...

and the bars were under a bit of pression but not that much either ... it kind of fit well if you get my drift ..

are you sure it's not a 14ft x 25ft ?

in that case your problem is solved ...

and make sure the diagonals are right before driving the poles down .. as it's the most important ones to get right for stability and strength .. .



it is possible that it should be 14ft, i dont know, but my problem would be one, the hoops would meet the ground tubes at an angle,so either wouldnt go in or i would have to put the ground tubes in at an angle too, and 2 , the hight in the middle, would allow me only just to stand , where as at 12.5 ft both problems seem to be solved, but what worries me is , is which way would be strongest as far as side on winds go., so i really am unsure still. the problemis is that most people buy there polyts new, and with them comes instructions telling you how widw apart to put the ground tubes, so in general people probably dont take alot of notice as to how much pressure they have to put on the bars to make them fit into the ground tubes, i dont man downwards pressure i mean side ways pressure, for example did there hoops fit straight in with no sideways pressure or did they have to push the hoops in a foot so that they fitted into the groundtubes. it is possibly something that if following instructions to set measurements, that would not be noticed, but if anyone can recall, then that wuld be great

[Smooth Hound]

Morning SH,

aye they're supposed to be under tension, If your interested A mate of mine is making one out of plastic pipe and I'm following it on my blog, also there's quite a bit about polytunnels on Thurston Gardens blog http://www.thurstongarden.wordpress.com/

Good luck, Paul

iwould be interested to see this plastic pipe polytunnel,but couldnt see anything on the link about plastic pipes. is there somewhere else to read something about it ?

[camillitech]

Morning SH,

aye they're supposed to be under tension, If your interested A mate of mine is making one out of plastic pipe and I'm following it on my blog, also there's quite a bit about polytunnels on Thurston Gardens blog http://www.thurstongarden.wordpress.com/

Good luck, Paul

iwould be interested to see this plastic pipe polytunnel,but couldnt see anything on the link about plastic pipes. is there somewhere else to read something about it ?

Hi SH did you try here http://lifeattheendoftheroad.wordpress.com/

this was it a couple of weeks ago



but there are more up to date pics on my blog above. Its made out of old fish farm feed blower pipe, old water pipe is the same. there's allot of it about just now with all the upgrading of water treatment plants to meet EC regs. I've just been given 470m of blue stuff, all I've got to do is get it down the hill

[Smooth Hound]

so its water work people you would need to speak to,

[camillitech]

Aye SH,

I dunno why but when they upgrade these treatment plants they put in a temporary overland supply. When they did the one on Raasay they laid a 90 or 100mm one it must have been 1/2 a mile long and some of my mates got that. Then about 6 months later they laid another 200m length of 63mm and another friend got that. Then I managed to get one off Skye, though I've already got lots of the ex fish farm stuff which I've used as ducting for my wind turbine etc. I read in the local paper just the other day that ROK (the company that did the one on Skye and Raasay have been awarded the contract to do several more throughout the highlands. So there must be miles of it somewhere

Cheers, Paul

[Marc]

In reply to the original question; in my experience it doesn't really matter. If you would like a bit more height then put the gound tubes a bit closer together, but do put them in vertically whichever way you go. The small tunnels are quite forgiving, very low tech

[Thurston Garden]

SH - both my tunnels have straight sides (about a meter high) and in both, the ground tubes were knocked in plumb/straight up and down. Perhaps if your hoops are curved, rather than straight sided, the ground tubes should lean inwards?

As Marc says, a smallish tunnel is likely to be quite forgiving, but if you have already received your polythene then make sure it's going to be wide enough if you make it 14ft and ordered polythene for 12ft!

Paul - thanks for the plug! I read all of your blog yesterday and was almost late for a cash earning opporchancity as a result Am gonna put you on ma blogroll!

[Smooth Hound]

Thanks for everyones advice

[Thurston Garden]

Remember and post some pics when it's done! We like pics....

[camillitech]

Paul - thanks for the plug! I read all of your blog yesterday and was almost late for a cash earning opporchancity as a result Am gonna put you on ma blogroll!

Thanks TG, glad you enjoyed the blog and good luck with the MOT

Cheers, Paul