Look around Alberta and see what has survived in the long run. Then ask the owner what type of problems if any he/she has had. DonÂt wait to long, GH activity will be picking up, it has already started down here.

John

Look around Alberta and see what has survived in the long run. Then ask the owner what type of problems if any he/she has had. DonÂt wait to long, GH activity will be picking up, it has already started down here.

John

We have horrible winds here too, but we modified our Harbor Freight and anchored it well, and wind does not seem to be a problem. It is sheltered by our house on the north, which no doubt helps. I really don't advise anyone to build a HFGH without making the modifications discussed in posts here, if it will be exposed to any wind.

I've been trying to get a better understanding of how the HFGH handles snow load (I have a blog about ours, and sometimes I get questions about snow, and I'm frankly clueless here in sunny New Mexico.) You may already have found the posts I'm thinking of, but there seems to be mixed experience with snow load questions. Some say 8" or so slides off without a problem; one person posted a roof stud failure at about 10". The unsupported center of the roof studs seems to be the weak point.

My guess is it's probably not good to depend on the HFGH to handle heavy snow loads without adding some kind of interior bracing, unless you know you'll always be there to prevent heavy accumulations (and you have to sleep sometimes, don't you?) However, I really don't know if other greenhouses have a better record. One poster here, Birdwidow, has stated that the curved eaves on her Cross Country greenhouse allow the snow to slide off more easily, but that shape also makes it more difficult to install bubblewrap insulation inside. (Maybe she'll pop in here in case I didn't state that quite right!)

I would think polycarbonate panels would be a much better choice than glass because of damage risk from hail (and better insulation too.)

I think John's advice is good. How about contacting somebody at the Alberta Orchid Society? I'll bet those members have greenhouses, and maybe they could share their experiences with you.
Orchid Society of Alberta

I have a 12' X 35' x 12' tall greenhouse, and my best advice to you is to go wider than 12'. There is not room to put a center aisle at that width, and I have wasted space down the center of my greenhouse. I pile the plants in deeper along the sides, but it makes it more difficult to reach the ones along the back sides.

My DH built my greenhouse about five years ago. It has double poly walls separated by an inflation fan, and 8mm twinwall polycarbonate ends. There are propane heaters at each end but we generally heat with electric heaters because it's cheaper here than propane. We easily sunk $5000 into it the first year and that was with the frame only costing $90. I could have probably done it cheaper but bought "greenhouse exhausts" and other items specifically made for "greenhouses", instead of listening to my husband and going a cheaper route. :) Live and learn...

We are in an extremely windy area and our greenhouse has held up well through high winds and hail storms. We get very little snow but what little we have had has slid off easily. We're in Zone 7 and don't get real cold winters. My best investment in keeping my heating costs down has been buying a solar pool cover. I highly recommend them.

I am a firm believer that you pay for what you get.
I waited until I had enough money and purchased a heavy duty greenhouse. The company is Atlas, they make small sizes and commercial GH's. I have never had a problem with storng winds or lots of heavy wet snow.
Something to keep in mind, when you put a building on your property, you may need a permit. Sometimes they may ask for documentaion regarding how stong the GH is based on an engineers evaluation. I can tell you that Atlas had what I needed to get my permit and put up my GH. This was just for a hobby greenhouse in my back yard.
I have said this in the past, you do not want to have a GH full of you best plants and then the wind or snow crushes the top - it is worth spending a little more knowing you have the strenght to hold up in all conditions.
My 2 cents
Mike

I've been doing the same research online and have come across a greenhouse kit by Yardiac that is virtually unbreakable. We too have high winds, hail, ect. Things that greenhouses just flat don't stand up to that well. I believe the link I've provided (for easy set-up click here) may be a little smaller than you're looking for, but if you search around their site I'm sure you can find the dimensions you're looking for! :) happy gardening!

Here is a link that might be useful: for easy set-up and simple moving

I would agree with Mike wholeheartedly, you get what you pay for.
That said, my greenhouse has a taller solid insulated wall on the north side of it. Since our growing season is relatively short and the winters long and cold this seemed to be the best option for me.
We used triple paned poly and it has stood up very well with cedar 2x4 bracing every 20 inches. We get plenty of snow and it really does not accumulate on the greenhouse. Just an hour of sunshine and it warms up inside enough that the snow slides right off.

I'd also recommend building as big as you can afford. Once you get going with using it, you won't have too much space.

There are a lot of books out that describe different plans for building a greenhouse. I will admit I did have a lot of resources on hand so my biggest expenses were the polycarbonate and the watering/electric systems inside the greenhouse.