Author Topic: Polytunnel Erection (Read 5422 times)

HeronsReach · « **on:** March 01, 2010, 10:10:58 pm »

Ive bought a second hand polytunnel. I took all measurements from it before I took it down. The only bit I couldnt take was the ground spikes which were concreted in. They were 47mm o/d and were out of the concrete 2ft. I've found some scaffold tube which is 47mm o/d, but i need an idea of what length goes in the new concrete??? An advice??? Any other tips would be helpfull Thanks

Eagledance · « **Reply #1 on:** March 02, 2010, 08:20:37 am »

Hi

good luck!

My tunnel doesn't have concreted in tubes but opnes with a foot plate which are in abouit 1 1/2 feet and back filled with soil.

Other tips - get help! Allocate lots of time - my tunnel is 12 ft by 6 ft and took me 4 weekends with help to get up!!
The polythene cover is tricky to get really tight - mine flaps a bit in the wind but has survived 1 year in very windy North Queensferry so must be ok!!

Ed

northfifeduckling · « **Reply #2 on:** March 12, 2010, 05:21:03 pm »

Ours is not concreted in, either, just dug in deep. Should be enough (I hope!). We've had the frame up for a year - when the weather was right OH broke his shoulder, so cover yet... Hope to get it done soon!

HappyHippy · « **Reply #3 on:** March 12, 2010, 06:27:08 pm »

I would avoid the whole concreting in malarky - base plates with u clamps looks to be the easiest (and temporary- see the other post on polytunnels and planning permission) way to go.
Here's a link to show you what I mean - same thing as Eagledance has
http://www.premierpolytunnels.co.uk/prod_list.asp?level_id=22&level=3&pgno=1
Hope that helps,
Karen

Declan · « **Reply #4 on:** March 13, 2010, 10:58:04 pm »

Herons Reach-
Further to the above posts it really depends on where your house will be sited. The whole concrete idea is more to hold the tunnel down rather than hole it up. Once the plastic goes on there is quite a bit of upward force produced which acts to suck the tunnel up. As the plastic on the tunnel is taut the force is transferred to the frame and hence the structure is "sucked" up. If your tunnel will be sited where there is a good degree of wind then I would be inclined to concrete in the legs. The legs can be bought relatively cheaply and they have a narrowed end. I would probably dig a hole say 1ft or 18 inches square by about 18inches deep. Drive the leg into the centre of it and fill the hole with concrete. You could use the "post crete" type of stuff from any builders providers wherre you only need to add water. There is no need to mess about with gravel and sand etcc.

Declan

Declan · « **Reply #5 on:** March 13, 2010, 11:00:15 pm »

Just a small note to add- if the tube diameter is 47mm then it must be a reasonably big house- therefore perhaps the concrete would be a little more important than on a smaller house where less upward force might be produced.