Allotment Gardening Advice Help Chat

Chatting => Design and Construction => Topic started by: Urbanite on April 02, 2016, 17:25

Title: Skinnin` a Tunnel...?
Post by: Urbanite on April 02, 2016, 17:25
Got a 15 x 8 ft Citadel PT to erect over the next coupla weeks, reading the instructions it recommends concreting in the foundation tubes if on an exposed site...fair enough.What I can`t get my head round though is if I concrete the tubes in, how do I trench the cover in around the foundation tubes... is this just me having a blonde moment, or what? ???
Title: Re: Skinnin` a Tunnel...?
Post by: New shoot on April 03, 2016, 13:39
I can't work that one out either  ??? You need the cover trenched in close in tight to the frame, or it will flap in the wind and eventually tear.  I'd give them a call and ask for advice  :)
Title: Re: Skinnin` a Tunnel...?
Post by: sunshineband on April 03, 2016, 16:17
I shall be interested in the solution too, as we are planning to install a tunnel at the end of this season, and our site is extremely exposed.

I have seen a couple of tunnel skins on our site shredded in the recent storm, so am determined to do it "right"
Title: Re: Skinnin` a Tunnel...?
Post by: Urbanite on April 03, 2016, 17:38
I can't work that one out either  ??? You need the cover trenched in close in tight to the frame, or it will flap in the wind and eventually tear.  I'd give them a call and ask for advice  :)
think Citadel have gone under....they opened an ebay store last year which is why i think i got a 400 odd pound tunnel for less than 300, the websites not updated and the last review of them i seen was some poor woman saying they`d took her money and run
Title: Re: Skinnin` a Tunnel...?
Post by: Urbanite on April 03, 2016, 18:04
measured the foundation tubes 18", you need 3-4" above ground, the cover is trenched at 12" deep, 2" away from frame, this leaves me 2-3" of concrete... not a lot really.Think what I`m gonna do is pop to wickes tuesday morning buy 8 breezeblocks(the ones with holes in?), set the foundation tubes in these  at 2" deep with a sand cement ballast mix, drop em into pre dug holes and then another inch or so of concrete on top of these...I garden literally a stones throw from the banks of the river Mersey on sandy soil so this has gotta be secure
Title: Re: Skinnin` a Tunnel...?
Post by: sunshineband on April 04, 2016, 19:48
A shame they went under, but, as you say, you got a bit of a bargain.

Like the sound of the breezeblock idea ... we are on a flood plain which is very exposed to high winds, so keeping a tunnel attached to the ground will take some solid fixings.

Hope it works for you!
Title: Re: Skinnin` a Tunnel...?
Post by: jezza on April 07, 2016, 22:57
hi we used to make concrete blocks  9x9" with the support to one side so that the outside edge was 2"from the side then the block as set slightly back in the trench this brought the cover level with the frame   then we put the cover on filled the trench then jacked the frame up till the correct hole in the frame was at the right height in the support then a bolt went through to hold everything in place  the last one put up as jacked up with hydraulic rams 180 x 40 foot polytunnel tensioned in 15 minutes    jezza
Title: Re: Skinnin` a Tunnel...?
Post by: Urbanite on April 08, 2016, 18:22
Frame up and door frames fitted, ended up not going with the breezeblocks...frame went up tuesday, simply knocked the foundation tubes in with a mallet, making sure everything went in square, built the frame.Went back wednesday dug out around the back of the tubes to the full depth then used a hand trowl to excavate round the front where the skin will be,,re-checked  that still in square,filled hole a third full with water and used just over half a bag of post-crete to each hole.One post at a time, working across the tunnel...we also used rope on the foundation tubes of each arch, tying each opposite tube together so when each hole was dug the outward pressure of the arch`es didnt move the foundation tubes...seems to have worked.
Title: Re: Skinnin` a Tunnel...?
Post by: grinling on April 12, 2016, 22:39
are you allowed concrete on the allotment....might be worthwhile keeping quiet.