Pondering a greenhouse design

[RonCo]

I've been kicking around an idea for a small greenhouse and I would like some input on light levels and growing conditions I might expect for orchids.

The plan is to build a small lean to greenhouse to cover a pair of east facing double wide doors I have in my workshop. The finished design would be like a window greenhouse but extend down to the ground.

The attached picture shows the pair of doors on the east side of the shop, you are looking towards the south west. The trellis is not there now. Some rough dimensions of the gh would be 6' wide 4' deep and 7' high. Current thoughts are to use some form of clear glazing, twin wall polycarbonate would be my first choice. Heat would come from the open doors to the workshop which is heated all winter.

I'm just curious how much light I might expect and would it even be worth my effort to build it. The gh would gradually be in the shade from noon on. Morning light would be full till noon. Any shrubs in the way on what would be the south side would be removed.

My current orchid collection is a whopping 2 cattleyas so I'm not to constrained in the light requirements.

Any ideas are welcome.

Ron

[Grandma M]

Ron
One suggestion. Those 2 plants will soon multiply like rabbits, especially with all the enablers around here. Better be thinking, more space.
Marilyn

[Ross]

If this were my setup, and if I were contemplating such a plan, and if I had the money, I would do it. Here are my thoughts (keep in mind I don't grow in a greenhouse right now but have in the past.) The "clear" glazing on top will yield a pretty high light level, even without sun. I would probably build a framed wall construction from ground up to level of lowest benches. This will help with heat. I would opt for either triple wall lexan glazing, or some system to insulate in winter. I would only grow cold growing orchids, such as Cymbidiums. Hope these comments get you thinking.

[RonCo]

Originally Posted by Grandma M

Ron
One suggestion. Those 2 plants will soon multiply like rabbits, especially with all the enablers around here. Better be thinking, more space.
Marilyn

Marylin

I'm thinking more space too. This little gh would be just a starter for this winter. I'm still dreaming about the BIG one right now.

I know first hand how the little green rabbit chids multiply. Years ago I had about 200 orchids in a greenhouse and I think I only bought about 10 of them.

[RonCo]

Originally Posted by Ross

If this were my setup, and if I were contemplating such a plan, and if I had the money, I would do it. Here are my thoughts (keep in mind I don't grow in a greenhouse right now but have in the past.) The "clear" glazing on top will yield a pretty high light level, even without sun. I would probably build a framed wall construction from ground up to level of lowest benches. This will help with heat. I would opt for either triple wall lexan glazing, or some system to insulate in winter. I would only grow cold growing orchids, such as Cymbidiums. Hope these comments get you thinking.

Ross

Thanks for the reply. I hadn't been thinking about a short knee wall but one insulated with foam would sure reduce the heat loss and cut down on the amount of glazing material I would need.

Good food for thought.

Thanks

[hosshead]

Hey there RonCo.
I am in NorthEastCentral OH and I can tell you this about Ohio in the Greenhouse;
Insulate like bejeezus, Make sure you have a decent Grey-day light source, have a plan for moving your plants back from freezable windows, and a radiant heat source for your warmth- I use 2 of those oil-filled heaters that look like radiators.
Oh, and electrical stability is very much helpful.
Like maybe a separate electric box on its own breaker is the ideal, when you think about powering a heater during those sub-zero days we get in Ohio.

I do something interesting with my heaters;
I get a LARGE, flat rock,(like a granite-type rock), and set it atop the heater. It will heat up and hold heat directly from the heater, I can spray the surface of that rock and then it "steams" the water into the air for added humidity, and I can shut the heater off for periods of time and the rock will still radiate the heat it has stored.
I have several blocky rocks that sit around each heater and will store heat, A pile of bricks will do the same thing.
And plants can sit on those blocky rocks and be spritzed down and bask in the warm humidity.
Plants can be arranged outward in "temperature tiers" to accommodate plant personal temp needs, and I get through some pretty dang COOOOOLD winters, and still manage some warmer growers.
I'm also willing to,(and set up for), bringing plants into the house during the super cold snaps, if need be.

I'd definately make it a bit larger and have that radiant heat source, if I were you. I have found that ambient heat from the house never quite cuts it.
And honestly, a space where you can have a little seat-room and sit and enjoy, even on the gloomiest of the grey Ohio days will have made the extra effort and cost so worthy. I like having a Bright-Lighted, plant-filled greenspace to spend time in, once the November blahs have set in.

I started out in Canada and find that the winters in Ohio can get nearly as cold, although less snow fall amounts.
(Yes, Even More than last years blizzard. LOL! )

[RonCo]

Hey Hoss

I remember heating an old single glazed glass greenhouse back in the 60's. I only had a 40000 but furnace and it would run constantly on those -20 nights.

My idea for the small gh size is just something temporary for this winter. A bigger one is in the thinking stages but it will have to be a freestanding affair. Right now I'm maxed out on garage/shop size of 720 sqft. Per the zoning people I can build a larger gh but it can't be attached to the garage. Zoning also allows an outbuilding (shed) of up to 168 sqft. The bigger gh could substitute for my shed. One or the other, but not both.

Heating is a concern and I'm going to do some calculations to see what it would take for my little 4x6 idea.

I was thinking even going to extent of adding some styrofoam panels over the glazing at night just to retain heat.

I did some computer sketches to see what this thing might look like.

The red frame would be the existing garage door trim.

An inside and outside view.

Ron