Designing budget greenhouses (light assisted) for 2 crops a year in Maine!

ive been recently mulling over design and buildout parameters for greenhouses on our small property to max out my caregiver plant counts (78 flowering plants). the idea would be to use a hoop bender jig and make some 12ft-16ft wide hoop houses using double inflated poly coverings for insulation. for simplicity and laziness id like to keep them single row and each end wall big enough to fit the tractor through. if i keep them as narrow as possible the better (leaning towards 12ft wide) but using tall sides so i can have at least a 9ft x8ft wide opening on both ends. ill be able to use a tiller and run straight down the middle each crop to amend the soil. Ive never built a greenhouse before and these certainly wont be commercial grade expensive setups. im thinking maybe 4 greenhouses each housing 20 plants, spaced 6ft center to center in a stripe right down the middle of each GH. each plant will have a 240w Quantum Board style light over it for light assist only. As many people know Maine has drastic swings in seasons which means a summer crop might see outdoor temps as high as 90s during the day and winter crops might see temps as low as -10F. the GH environment will need to be able to keep temps cool enough during summer and warm enough during winter crops but the RH not having massive swings from like 30% to 70% during each exhaust event. any ideas and advice would be greatly appreciated. and cost is a vital concern. we plan to set this up without massive upfront buildout costs. ill be doing all the work and build myself.

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Awesome good luck buddy can’t wait to see em!

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Honestly I probably won’t get to start on it until winter That’s going to make building it extra fun

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Things to consider:
1 snow load
2 heating
3 water freezing
4 humidity in winter
These are what I’m working on adding to my greenhouse kits, working on figuring out the load calculations for using geothermal. The heat of the summer is easy to deal with its the cold of winter that’s a bitch.
If you need help let me know.

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indeed, winter is the tricky part of the equation, ill have to bury the irrigation supply lines deep enough to keep from freezing. ive thought of using a kerosene heater that also doubles as c02 generation, ill need humidification and dehumidification and hopefully i dont need more than 50 amps per greenhouse.

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With 50 amp it will definitely be doable.

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im liking these little diesel china heaters but i dont see any cheap ones over 8kw. i might need a few in each greenhouse.

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Why not use wood burning?
A simple water bath with copper piping to coils and fans. One can heat multiple greenhouses.

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I ran wood for 5 years in 20,000 sqft. My life changed for the better when I switched to dinosaur bones. The problem is, when it’s cold, you have to load the heaters in the middle of the night, and you have to constantly source your fuel.

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I have one of those hoop benders, they work really well, I would recommend.

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Gas when available is a much easier option

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My god, cords and cords and cords. That just sounds horrible, and I’m not even considering cutting or spitting it. Just dealing with volume, and feeding.
You finally decided you wanted your life back! At least that what I imagine!

I thought I was saving money…

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Saving to lose!
I honestly have no concept of the cost to heat with wood. It was basically free in AK, and not so much in New York. BUT personal scale.
Obnoxious I’m sure! If not in money, than definitely in time.

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I’m talking about 4’ logs. Load only one time a day

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I don’t have the logistics setup for keeping wood burning stoves fed. These things have to be as automated and easy to maintain as possible since I work 50-60 hours a week at my normal job.

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I’m looking at going cmh instead of led.

Anyone know of cheap china 315cmh ballasts that have an rj45 port for a controller? I’ll need 80 of them lol. 20 per greenhouse. I think 315w cmh will do better at light assist then 240w quantum boards.

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Did u ever do this? I’ve been contemplating something similar but more of a dug in style