Hi there. Good luck! :-)

I pretty much posted the same question and didn't get much of a reply. A lot of people responded with building one out of PVC plastic, but i see too many collapsed metal ones here in MA to even think about PVC.

As you drive through the wet winter snow, take a look at the ones you see lying on the ground. Every one of them is a hoop house. I have never seen a gothic arch collapsed. It could be that there are just so few of them around, but it makes sense that a peaked roof will shed snow better than a half circle. Those hoop houses have a relatively flat top - a nice place for snow to accumulate.
I think you may have somewhat of an advantage with a narrow hoophouse. It seems to me like the wider ones (20 foot +?) are the ones that tend to fall under load. (Now that i dissed hoophouses, you'll get tons of replies saying how great they are..)

Your best bet for info is to drive around and stop in at the local nurseries. Seeing what they have and recommend.

I looked at farm-tek, and a local supplier that seemed to be used a lot by garden centers - Griffin Greenhouses. I think they have outlets in CT and eastern MA.

I ended up lucking out and buying a gothic arch at auction that had been in use by a wholesale grower. It lasted a few years for him so i am sure it will stand up to the snowload - I think the frame is 1.9" dia. Didn't check the gauge. The one i bought was set up 4' on center. They did have a few that were 5' OC. I am going to sick with 4' for peace of mind. Have yet to set it up.

Enjoy!
Poppa

I have a 12'x 28'GH that is double layered film. The hoops I made were out of two 10'lengths of ½" metal electrical conduit connected with a four way junction box (to form a cross connection). It has withstood 75mph winds and snow storms with falls of up to 18" but the snow usually slides off after about 6" build up. Mine is heated.

Only being 12' wide does make it taller (about 7') then one 20' wide. I did try PVC sch 40 on half and it snapped at the fittings.

This is my second year with a series of 'hoophouses'. I have 12 raised beds 4ftx8ft, each has 1" pvc sections buried at eight points along the edges. Into them I insert my 6 ft long arches of 3/4" pvc (came on a 50ft roll). Over that goes 6 ml plastic (three sections) with slits for ventilation. The three sections make it easier to open to water, weed, plant, harvest, etc. The snow slips off after it reaches 2-3 inches of accumulation. The hoophouses raise the soil temp at least 15 degrees and extend our painfully short growing season a month on each side (spring and fall). After frost is passed, I use the buried pvc sections to support trellises, bird netting, whatever the plants need (mostly vegetables and strawberries). My squash and tomatoes like the arches as support, instead of those ugly wire cones.

Here is a link that might be useful: netdiva's garden boxes

My first greenhouse was a 14x24 hoophouse from growitgreenhouses.com and I was completely satisfied with it to the point that I have since added two more of them onto the end making it a 14x72. I believe that they ship out of Ct. so that would be close to you.
I heated the house from the very first with an old barely adequate gas heater but after adding to the length of the house I double layered the poly and inflated it and greatly improved the heating situation with a much better heating system.
We don't get a lot of snow here but when we do it's usually early Spring and it's wet and heavy and when that happens I turn off the inflation blower, let the top poly layer collapse against the inner layer, turn up the heat, and the interior heat starts to melt the stuff. I also take a broom and push off the snow from the outside.
My house runs North to South and last year it withstood a wind that was clocked in town at 101 mph from the N.W. and did A LOT of damage. Down here in the creek bottom it probably wasn't quite that bad but still took a lot of trees and tree limbs out. This old hoop house just shrugged it off. Here we get lots of 60 mph plus winds.
This fall I am replacing the inner layer with Klerk's Kool-lite poly which will help keep the heat down on warm sunny days, distribute the light evenly, and has anti-condensation properties. Condensation really hurt my plants last Winter with water more or less continually dripping on them. I kept two fans going 24/7 to try to keep them as dry as possible but even that wasn't enough.

Bob

We were luck to find a farmer who had thirty unused hoops he was willing to sell us for $10.00 each. We now have seven 12x30 hoop houses made of gal. steel hoops and they've lasted over ten years of Cape Cod winters including the 2005 3' blizzard. My husband put the laterals high up the hoop and it has been perfect for in ground tomato growing.
He starts with compost, fertilizer and the roto-tiller. Then he lays down the drip irrigation which is attatched to the battery operated timer from Home-Depot. That gets covered with black plastic film. When the temperature is right he cuts a hole in the plastic and drops in the transplants. We get ready by tying long lengths of venetian blind cord from the three laterals then tie the cord to a strong leaf on the plant. As the plant grows up we swirl the stem around the string. This movement is enough to set some flowers. A quick walk through the tunnel dragging your hands along the strings is like Tom and Huck clicking a stick along the picket fence.This is the only support we use and many of the plants grow five to six feet tall.

We've seen the hoops for sale in the Griffin Catalog but we've never taken a close look at their product. Make sure you get a single span, heavy gage hoop. Our first hoop house was from a kit and the hoops were in sections. We were away during a heavy snow fall and the whole house collapsed under the snow load. After that experience we talked to the farmer about his hoops and everyone was happy with the deal. Transporting the hoops in our 6' pickup truck was another experience altogether.