Hi There, I would like to build a polytunnel greenhouse but can't seem to track down any obvious place that sells the poles/rods/arches (not sure of the correct terminology) that form the skeleton. I'm looking to build a 10 ft long by 8 ft wide by 7 ft tall (approx) tunnel. Anyone know of a supplier in the lower mainland of BC? I'm in Gibsons on the Sunshine Coast so if you know of one on the Coast, that would be perfect (but I'm not holding my breath ;-) Many Thx in advance for your help, MXB
There are several companies in the Fraser Valley that specialize in these structures. Like you, I'd not hold my breath for a supplier right on the Sunshine Coast. The market is quite large in the Valley thanks to the commercial nursery industry there. I used one of these companies, not saying he's the one for you but you can snoop thru their site for a start...lots of ideas for hobbyists as well as larger growers. http://www.steelgc.com/
I believe Fraser Valley Greenhouse Supplies in Chilliwack carried a line of those type of greenhouses. I have built a couple smaller ones (like 8 by 10') just using the white PVC for irrigation. A few elbows, T's, and some ingenuity it can be pretty straightforward. Use the proper glue for the joints and then a trick to attaching the poly is to use some of the same diameter tubing as your ribs and support posts, cut a 2 inch long piece, slit is on one side and remove about 20% of the rest, so you have an exaggerated 'C' shape, use this to clasp the poly over the posts and ribs as necessary. Making a hinged door can be a bit tricky but with enough rigidity in the end framework it can be done.
I have a slideshow showing the erection of my own tunnel greenhouse each spring. The greenhouse is about 12' long and 10' across at the bottom, maybe 8' high at the top (the crosswise pieces are formed by joining two 10' pvc lengths, and high school math will tell you the height if you know how far apart you want the sides to be at the bottom). Do not waste money buying anything commercial: pvc pipe from Home Depot - the thinner the better, since the thicker it gets the more likely it is to break as you bend it - is OK. And the best covering in the world in from Northern Greenhouse Sales (I think - can check) in Manitoba, run by one of those guys who builds spare rooms out of disused tractor tires, a man after my own heart (and presumably yours too, since you live in Gibsons). My covering has lasted a decade with no signs of the slightest wear. But remeber, this type does not retain heat and so even with a heater you will just barely be able to keep it above freezing at times in the spring. And they are not kidding when they say to ventilate them. When I first built it, I closed the doors and left it closed all day on a sunny day. The trial plant was dead as a doornail: the temp was about 120 F and the humidity was 105%. Now I have a self-opening vent at the top (Lee Valley tools sells the automatic opener thing that you need to built the vent) and during sunny days it never gets above 90 F. Of course I need to have a box fan running and the doors open just the same ...
Soccerdad, shame you don't have that slideshow up on the web ;-) I'm leaning strongly towards DIY after seeing some of the prices that you can pay for what seems like a simple structure. We have been wondering about the ventilation aspect so thatnks for the tips on that, Cheers MXB
If I can figure out how to do it, I will send it to you on Monday (it is currently on my work computer for a reason that I can't recall). But maybe I need your real e-mail address, so sent me a p.m. giving it.
We built a 25' by 10' wide hoop house 4 years ago and are very happy with the results. We based our hoop house on the plans found here -http://cru.cahe.wsu.edu/CEPublications/eb1825/eb1825.html. We modified it by putting hinged doors on each end which are staked open for ventilation when needed. You can also raise the sides for additional ventilation. With only single wall poly, it does go below freezing in the winter, but we can still grow greens in there fall, winter and spring, and tomatoes and peppers in the summer. Once built it is easy to take down and move if necessary- takes two people about 2-3 hours.
