Using windbreak netting on top to protect and tightening cover polytunnel

Hi All,

I am new on this forum. I am David from the Netherlands.

I was using this forum to get information about the blowaway polytunnels. Thank you all for sharing information and photos.

After a while of thinking and looking on this forum. I have decided to buy a ploytunnel (6x3 meter). It tooks me 2 afternoons to put it on my allotment.

My polytunnel has stood up last week the winds of Doris 130 km/h. But I find the cover not tight enough. The wind catch the cover every time so I want to put a netting on it for tightening.

My question:
Is it a good idea to use debris windbreak netting on top of the green cover to protect the cover from wind and UV. The netting is 4x10 meter and gives 30% shadow and wind reduction.
I want to cover the whole polytunnel on the outside as a extra protection for the green cover and to get the cover more tight against the hoops, so the cover will last longer.

but I am afraid for too much shadow. What do you think?

Many thanks,
David


Debris windbreak netting

 

Hello David and welcome here to GC in the UK.

Ok, good and bad news, bad news first. These covers are rubbish (when compared to polytunnel plastic that is) and they will last 2,3 or even 4 years.

Good news is that the frame is excellent and I see you have the version that has three ridge poles, so it is super strong and will last well. The cover looks to be a good fit but will always blow in and out with the wind, it does not stretch like polytunnel plastic does, so does not become too tight.

I'm guessing that you "trenched" the cover in, that is you dug a litle trench around the tunnel and laid the cover into that and replaced the soil on top? If you stamp this down all around, it will further tighten the cover.

I see you have made and fitted a door frame, get a door made and fitted too as soon as you can, the zip up doors are rubbish and will soon fail at the zip.

But you still have a fantastic frame, you will need to recover it with polytunnel plastic in a few years but then it will be tight with a great frame so your investment is not lost.

Do not bother with the debris netting, the extra shade it will give inside your tunnel is not a good idea. Live with the tunnel how it is and be prepared to replace the cover when the present one goes.

You have made a very tidy job of it, well done you !

Steve...

 

Thank you wiseowl for the tag.

Hi Steve,

Thank you very much for aswering my questions. Your polytunnels posts are wonderfull with detailed photos many thanks for that, it helped me a lot with purchasing/ choosing this type/model of polytunnel and securing/building the frame.

I have already trenched the cover, I will stamp again to tighten the cover.


If this cover last 2 years it will be great, than I will replaced it by proper plastic polytheen as you suggested.


This polytunnel has 1 metal door and 1 large zip up doorway. I will not use the zip up. I have closed the zip up doorway and trenched aswell.

I am thinking to place/build a dubbeldoor on the frame with netting and plastic or just a window for extra ventilation.


I will post the poly progress later....

Many thanks!!!

David

 

Your more than welcome David and I'm glad that documenting my polytunnel builds has helped you with yours.

It looks like you have a very tidy plot there, it would be great to see more through the season..

Steve...

 

I don't see any timber battens securing the cover to the door frames. When they are added that will enable some slack to be dragged towards the ends. Using anti-hotspot tape on the frame also makes the cover tighter (as it will slightly increase overall size of frame).

 

Thank you for your reply Scrungee.

I will add the timber to the doorframe, the idea is to build a window for extra air circulation in the summer. On the outside I will cover the frame with netting

I didn't use anti-hotspot tape, instead I have used pipe insulation (that grey foamy stuff) around all the hoops (jenny's idea) 48 meter in total for £17. (See photo)

My plot is 300 m2. Enough space for growing and gardening, I will place more photos through the season.

Valuable info and experiences on the GARENERSCORNER!

 

When you replace the cover i`d recommend using double poly and a small blower. Better insulation, automatic cover tightness. Poly loosens in hot weather and tightens in the cold. Inflated to 0.5" inches of water the cushion of air will support 370kg, good for snow. When a strong gust of wind hits the poly it absorbs the impact like an airbag and reinflates instantly. Poly that is allowed to flap in the wind wont last very long

 

I used webbing straps with 18" ground anchors, loosely tied so not to bend the plastic but will not allow it to expand in the wind.
3 on a 9m tunnel