poly tunnel position

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happyigloo
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poly tunnel position

Post: # 204036Post happyigloo »

Hello

OK Getting a Poly tunnel put in. Actually going to build one myself.

Just having a debate with a friend who'll be helping me. He thinks I should put it 'side on' into the wind because of the curved wall. I think it should be 'end on' to the wind so the thinnest end is facing the wind..

I can see the logic of both arguments. Any opinions?

Thanks

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Odsox
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Re: poly tunnel position

Post: # 204041Post Odsox »

From personal experience I don't think it matters either way.
Mine are north/south so are broadside to the prevailing wind, except the ends are pointing out to sea, and get clobbered by southerly gales from that way.
I suppose if the strong winds ONLY came from one direction and it didn't matter as far as the sun/shade was concerned, I would probably choose to be end on to the wind. In the winter I fix a rope guy from the exposed end door frame top to a ground anchor and it has so far put up with 100mph winds. It's also survived broadside winds the same, but it does make the polythene balloon rather alarmingly which it doesn't seem to do so much end on.
Tony

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Re: poly tunnel position

Post: # 204061Post Green Aura »

If you plan siting it somewhere that's very windy then you need to consider carefully what you get. We get similar, 80+mph winds to odsox. The polytunnel is front on to the prevailing wind as it was the only place we could put it. We bought a 35mm frame (they're usually 25mm) and the storm bracing and crop bars, which help to make it more rigid. We also bought the heavier weight polythene.

All the locals shook their heads and smiled knowingly when they saw the polytunnel - we were told it wouldn't last the winter. It's now two and a half years old and although I'm not sure the polythene will last another year (we knew we'd have to replace it more often than most) the frame is absolutely sound.
Maggie

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Life shrinks or expands in proportion to one's courage. Anais Nin

happyigloo
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Re: poly tunnel position

Post: # 204066Post happyigloo »

Hey thanks guys.

I can pretty much put it anywhere. It's a blank canvas with no shelter at all. I'm on the west coast of Ireland so we get our fair share of winds.

Still a bit unsure of what to do. Am leaning towards 'end on' into the wind. It would blend in the site better. Although there is a slight incline if I put in there. Any idea if thsi will be a big problem?

Thanks very much for your help.

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Re: poly tunnel position

Post: # 204069Post Green Aura »

The info with ours said it could slope lengthways but not sideways - if that makes sense.

So that might be your deciding factor.
Maggie

Never doubt that you can change history. You already have. Marge Piercy

Life shrinks or expands in proportion to one's courage. Anais Nin

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Re: poly tunnel position

Post: # 204082Post Odsox »

Mine are on a slight slope lengthways, and I have to say that although all the literature says it's not a good idea, I find it to be an excellent idea. As the heat always flows to the top end there is a hotter end and a cooler end for choosing where to plant different crops, plus it really helps the ventilation on calm days as the heat naturally flows out of the top end forcing cool air into the bottom.
Also when it really rains hard there is natural drainage which stops the tunnel from flooding.
It really is a benefit and I can't for the life of me understand why the instruction books consider it to be a disadvantage.
Tony

Disclaimer: I almost certainly haven't a clue what I'm talking about.

happyigloo
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Re: poly tunnel position

Post: # 204103Post happyigloo »

Hmmm... It's sideways. I could with a bit of hard work get it level. My soil is full of rocks so it's not an idea that fills me with joy. I'll already be double digging a good bit.

Anyone know the reason why sideways is bad?

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Re: poly tunnel position

Post: # 204111Post Odsox »

I think it's probably down to the building of it.
It would be a bit of a job to get anything level, especially the door frames and the cross members, and if the slope is quite pronounced it would be a job to fit the side hoops to the ground anchors as they would have to be installed to suit the slant instead of vertical.
Not an impossible task, just making it more difficult .. especially if you've never built one before. :scratch:
Tony

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happyigloo
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Re: poly tunnel position

Post: # 204121Post happyigloo »

It's not that pronounced. I just hate digging.

I was just onto a Polytunnel crowd there about the plastic. The advice they gave was to always position 'end on' (gable end) into the wind. They also said that inclines are best length ways rather than width. Typical!

They did say if I'm building it myself I can adjust the hoops to accommodate this. If I was buying a tunnel it would be a bigger problem.

So I think I'll do the digging if the OH is happy with position.

Thanks for the advice everyone. :)

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