Looking for large greenhouse ideas- for heavy snow region

[fireweed farm]

I'm hoping for some ideas from anyone who has had luck with larger greenhouses in snow country.
For a few years now I have been looking for greenhouse options- plan is around 25' x 30', more or less. Have only been looking at poly covered steel framed hoop houses. Haven't considered wood framed, yet.

It would need to be able to withstand heavy snowfall and heavy winds. I don't want to be a slave to shoveling it off- that said though to help with snowload I plan to build it up on a 2' wood or concrete base- so that snow can be cleared from around structure with a tractor. When it starts piling up around the sides it can cave in that way. Supposedly that is the main problem with snow.

The plan is to grow tomatoes and melons etc in summer, but more importantly have fall and spring crops of hardy veggies like greens that can withstand cool temps. No electric heat or lights are planned here.

I'd like to get the ball rolling for a spring build.

Any ideas would be appreciated.

[Callieslamb]

We looked at hoop houses. They are the most common season extenders out there now so there has to be a reason for it. We like to do things for ourselves. The connectors used to attach the plastic to the hoop frame were 2/3 of the total price. We decided to go with wood since I could have a larger greenhouse that way and we could do all the construction ourselves, not spending extra to attach the plastic. It has not had to withstand a snow load yet of the proportions that we can get here. It did just fine with an 8 inch dump last year. All the snow just slid right off. I don't like the idea of replacing the plastic every 4-6 years. It's a big job and I don't want to do it any more often than I have to. We bought some used polycarbonate panels last year. We haven't installed them but are sure that with adequate support they will withstand whatever snow load our climate can foist upon it. We might have to add additional roof supports. The ones we have now are 4' apart. You should consult with a company that builds hoop houses in your area. I'm sure theres a way to build one that will withstand your weather and they would know the specs for that. I ended up with a 14x20 for about $700.

How/what to do depends on what you want to end up with and how much money you want to spend. If you are going to do the work yourself or not. There are plenty of hoop houses here that seem to withstand all our winds and snow. If you have the chance to add electric, you might want to do it anyway. A simple bulb can go a long ways towards keeping new seedlings warm. And a fan could be a really big help in the summer. I didn't put it in and really, really wish I had. I have no plan to heat the GH, just lighting sometimes would be nice. We added a simple overhead irrigation system on a timer - that has been a real blessing.

I love piddling out there in the winter.

[idigbeets]

I built a 20x40 wood greenhouse w /poly film covering for under $1200. If you want polycarbonate panels for the roof, would add another $1000.

[Bluebird]

We found a small hoop house which we put in 3 years ago. Had one really heavy snow winter not last year but the year before. It sits in a field open to the winds from all angles. Have never had to shovel it off, the warmth it creates inside melts off the snow on top and slides off the rounded edges. Have some issues with needing to patch a couple of rips in the plastic at the edges where it is under the wiggle wire channel but I think that is because I didn't secure the roll up on the north side well during a really windy couple of days this spring and it ripped 2 - 3 inch rips which I readjusted. I found it while driving past it a number of times and realized that the owners where not using it, got it for less than $100. Easy to take down, put up, and the plastic should be good for at least a couple more years. We did buy the greenhouse plastic.

[ronbre]

mine is small but it is double wall polycarbonate with extruded alum frame, will stand up to any wind or snow load..it also has an automatic vent.

there are online sources for 4x8 sheets or rolls of polycarbonate avail...as well as vent arms and framework..

another way is to use salvaged glass, like used sliding doors, etc..double wall at least

[JanO]

I have a freind up in Canada who lives out in the middle of nowhere, and he has a bio-dome type greenhouse. It's huge, probably much larger then what you want, but we were up there last winter when there was snow on the ground and it was warm. He grows veggies pretty much all year of some type. I personally don't know that much about them, the cost, or anything specific, but I was impressed with it and how sturdy and effecient it was.

[Wolf mom]

Why don't you look at building a solar green house since you don't plan on using heat?

Here's a good all inclusive book: The Solar Greenhouse Book by James C. McCullagh. There's a professor at Northern Arizona university (Lot's of snow!) that teaches how to build one and grows vegies in mid-winter in one with no additional heat. It's all about glazing, sun direction & insulating the north side.

I'd think long & hard about a plastic covered hoop house considering the investment & work involved, how soon you'd have to replace the plastic and how long it'd extend the season for you. Myself, I'd rather spend a little more money up front, do it right & move on to other things.

I know two families that have built greenhouses attached to their house and they heat up so well they use it to supplement winter heat in their home.

[Maverick_mg]

This is what we are growing in now. It will handle the snow. We were not originally going to have lights, but after trying to pick things many times in the dark, we opted for electricity. That allowed us to do two layers of plastic and add a greenhouse fan to blow in between the layers, it adds insulation and makes the whole thing stronger. Plus two layers of plastic can add another 5-8 degrees to outside temps. The raised beds can add another 8-10 degrees and on really cold nights/days, frost cloth on the beds can add another 3 degrees. So on the best days, inside greenhouse soil temps can be 16-21 degrees warmer then outside air temps.
The paths are limestone to add thermal mass and the north wall will be covered in a reflective insulation and lined with shelves that will hold black painted milk jugs filled with water that will also act as thermal mass. The idea is they will store heat all day long and as the temp inside the greenhouse drops, the cooler air will draw the warmth out of the milk jugs and path. They won't heat the greenhouse, we might add a wood stove for that, it will just slow down the rate at which it gets cold. (hopefully)

[Callieslamb]

Another thought. When we side ours with the polycarbonate, we're not putting it on the north side. No sunlight comes in on that side so we'll just put wood or if we can find it cheap-vinyl siding. We could also insulate it. It would only be for the upright portion on the north side wall. That will help with the weight of snow piling up on that side. The roof above will still be polycarbonate.

[Copperhead]

If the snow is as heavy as you are implying . . . Forget a hoop house, go with an A-Frame!

Northern Greenhouse Sales - Bob’s Big and Little A-Frame Greenhouses

[||Downhome||]

Our plan is Gambrel style wood frame probably a poly cover to start.
The north side will have a hip roof off it and be a insulated room for our Fish tanks.
Situated East to west with only those sides and the south side and top glazed.
the room off the back will also serve to grow low light plants,propagate from cuttings and harden off seedlings.

[ChristieAcres]

We are planning to build a greenhouse using tempered glass and it will be heated with a rocket mass stove.

[Big Dave]

Hey I am putting mine up as you are writing all these things. Go to www.aunaturalfarm.com Paul and Alison Wiedger are the farmers and they use high tunnels in kentucky to grow 365 day a year. The book they have written is "Walking to Spring". The book details their experience with snow and frezzing temps in a high tunnel hoophouse. I am putting skin on my gothic style hoophouse this Wednesday(tomorrow) The covering I have chosen is from Farm tec. I called Norhtern green house sales and spoke to Bob. They sent me a sample of the product they sell. I then called Farm tec. Spoke to a young lady name of Katie and have recieved my covering today. Not even out of the box yet. My c channel and wiggle wire for my 25' X 19' ran around $700. I ordered polytarp rather than 6 mil plastic. The Wiedigers use a double wall covering on their high tunnels and the next one I build will be made that way. I hopefully plan on posting a how to with pictures very soon. Hope some of this helps.

[ChristieAcres]

I should have posted I was going to build a high hoop house but scored 70 pieces of tempered glass for a few hours of gardening consulting and extra seedlings/plants. The size is just 4" shy of 4 ft wide by 6.5 feet long. That represents the biggest expense now covered.

[Gianni]

[QUOTE=Maverick_mg;6256995]This is what we are growing in now. It will handle the snow. We were not originally going to have lights, but after trying to pick things many times in the dark, we opted for electricity. That allowed us to do two layers of plastic and add a greenhouse fan to blow in between the layers, it adds insulation and makes the whole thing stronger. Plus two layers of plastic can add another 5-8 degrees to outside temps. The raised beds can add another 8-10 degrees and on really cold nights/days, frost cloth on the beds can add another 3 degrees. So on the best days, inside greenhouse soil temps can be 16-21 degrees warmer then outside air temps.
The paths are limestone to add thermal mass and the north wall will be covered in a reflective insulation and lined with shelves that will hold black painted milk jugs filled with water that will also act as thermal mass. The idea is they will store heat all day long and as the temp inside the greenhouse drops, the cooler air will draw the warmth out of the milk jugs and path. They won't heat the greenhouse, we might add a wood stove for that, it will just slow down the rate at which it gets cold. (hopefully)
[QUOTE]

Milk jugs do not have a long storage life. I would look at two liter bottles, antifreeze jugs, bleach bottles and any other container that has a different type of plastic than a milk jug.
Your lay out looks great. What are your exterior dimensions?

[Maverick_mg]

Thanks! 20x20 are the od.
Thanks for the heads up on the jugs. We do plan to use mix of jugs, right now we just have more milk jugs then anything, we'll swap them out as more become available. Most of the materials we are using have been salvaged, repurposed, or recycled, so I'm sure we'll end up with more soon.

[coup]

a neighbor here in central wv spent thousands on a big green house,,,,,it is toast,,,,,i should get some pics..........

[fireweed farm]

So much great info here, thanks! I need to spend some time looking at it and checking out the websites.
Rocket mass heater = great idea.

[SolarGary]

Hi,
The first greenhouse listed here: Solar Sunspaces and Greenhouses Plans

Is intended for growing through the winter in Missouri with no supplemental heat. It was developed by the U of M extension service and has been in operation for 18 years -- no freezes in the winter, and no supplemental heat.

I'm in the process of building a scaled down one.
Solar Experimentation Thing in MT


Gary

[unioncreek]

I would suggest a hoop house with two layers of film with air blown between them. When I visited my son in Alaska there were quite a few of them that I could see.

Bob