# Greenhouses?



## Duck Slipper (Feb 18, 2021)

Actually posted on here some time ago that I thought S/T needs a specific category for Greenhouses. People with a GH would have experienced many questions coming up and be able to contribute...
I finally pulled the trigger on one. Actually made the down payment back in December...with delivery in June/July. Another manufacturer I was corresponding with was deliver in August, that was with a December order. Covid has been very good for their business.
Everyone’s experiences with their GH and the ice, snow and cold would be interesting. What kind of heat? How’s it holding up? Are you having to go sweep snow off your house?What kind of humidity are you running in the cold? How do you keep it up? We have about a foot of snow here in West Kentucky. Just some thoughts and musings...


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## NYEric (Feb 18, 2021)

My house is green!


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## Duck Slipper (Feb 18, 2021)

NYEric said:


> My house is green!


Mine also, I’m running out of room...BUT, from the photo evidence I’ve seen, I’m lagging behind quite a bit to catch up to NYEric!


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## Tom-DE (Feb 19, 2021)

NYEric said:


> My house is green!


That is a good one!


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## Tom-DE (Feb 19, 2021)

How big is the gh you are thinking of? Normally you don't need to worry about the snow on the gh roof. I never did when I lived in NJ. The snow just slid off the roof if too much... RH is easy to do in gh, most of the time, I just wet the floor if I want a tag more humidity.
I am thinking about a small/medium I/C greenhouse(if I want to pick up this orchid hobby again).


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## Duck Slipper (Feb 19, 2021)

Tom-DE said:


> How big is the gh you are thinking of? Normally you don't need to worry about the snow on the gh roof. I never did when I lived in NJ. The snow just slid off the roof if too much... RH is easy to do in gh, most of the time, I just wet the floor if I want a tag more humidity.
> I am thinking about a small/medium I/C greenhouse(if I want to pick up this orchid hobby again).


Already put a down payment on a 12x30, with a June/July delivery


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## Tom-DE (Feb 19, 2021)

That is a good size gh. and you have found yourself a big project for the summer.


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## Ray (Feb 19, 2021)

12 x 30 will take a few months to fill...

When I lived in Louisville (LaGrange), my GH was pressure treated 2x4's covered with a single layer of flat acrylic. Damn was that expensive to heat with 220V electricity.

When I moved to SC, I built a wood frame and covered it with an inflated, 2 layers of polyethylene. With the amount of sun there and a bunch of water-filled steel drums painted black, I hardly paid to heat at all.

When I was transferred to NJ, I copied the 14 x 14 Turner Greenhouse design, and also went with the 2 layers of film. We had natural gas, and I really didn't separate it from household heating, but I estimated the heating to be about $100/month over the winter.

When I moved to PA, I bought a Turner 14 x 18 structure. I covered it with 8mm twinwall polycarbonate. Unfortunately, there I had to use propane and that got really expensive - at the end, I paid $4500/year on a budget plan to cover winter heating costs.


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## Ozpaph (Feb 19, 2021)

holy! $4500/year. Im grateful for the subtropics. Cooling seems much cheaper.


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## Ray (Feb 20, 2021)

At least I could write it off to the business...


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## awesomei (Feb 20, 2021)

My greenhouse is 12 X 20. I built it myself with 1/4 inch clear Twinwall panels over both sides of a 2x4 stud walls. My roof is 1/2 triple wall polycarbonate translucent. Already gotten too small!


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## tomp (Feb 20, 2021)

Ray,
In your opinion/experience how did the inflatable roof compare with the rigid?


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## Duck Slipper (Feb 20, 2021)

Ray said:


> 12 x 30 will take a few months to fill...
> 
> When I lived in Louisville (LaGrange), my GH was pressure treated 2x4's covered with a single layer of flat acrylic. Damn was that expensive to heat with 220V electricity.
> 
> ...


 I am from Louisville and Lagrange is close to where I lived. I was raised in the East end of Louisville in the Westport Rd area.
I actually looked at building a treated lumber frame polycarbonate house last year but polycarbonate was so hard to get and actual plans also. Myself and friends are basic carpenters and thought that would be easiest...not so much. Then looked at building one out of windows, old and new. That turned out to be, not inexpensive. 
I have an unused 1000 gallon propane tank, so that will be my heat. I have natural gas at my home, but another meter is at a higher rate.
I have upgraded (recommended by others on here) to a 16mm triple wall poly. Probably going to use a Modine Effinity or Modine Hot Dawg heater but I’m not sure what size BTU, yet. Also, if a power outage Southern Burner used to make a very popular gas GH heater, but they went out of business. It required no electricity.
I have many questions and greatly appreciate any input.


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## Duck Slipper (Feb 20, 2021)

awesomei said:


> My greenhouse is 12 X 20. I built it myself with 1/4 inch clear Twinwall panels over both sides of a 2x4 stud walls. My roof is 1/2 triple wall polycarbonate translucent. Already gotten too small!View attachment 25674


Awesomei,
What kind of heat are you using? Emergency heat?


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## Ray (Feb 20, 2021)

tomp said:


> Ray,
> In your opinion/experience how did the inflatable roof compare with the rigid?


I presume you’re referring to insulation. The two poly layers, inflated with outside air, was quite good, but less sturdy in an environment with branches falling from trees, which I had in PA. The polycarbonate looked better in a neighborhood situation.

Multiwall polycarbonate is very good - the thicker and more walls, the better. If I was building a greenhouse today, I’d go that way.


Duck Slipper said:


> I am from Louisville and Lagrange is close to where I lived. I was raised in the East end of Louisville in the Westport Rd area.
> I actually looked at building a treated lumber frame polycarbonate house last year but polycarbonate was so hard to get and actual plans also. Myself and friends are basic carpenters and thought that would be easiest...not so much. Then looked at building one out of windows, old and new. That turned out to be, not inexpensive.
> I have an unused 1000 gallon propane tank, so that will be my heat. I have natural gas at my home, but another meter is at a higher rate.
> I have upgraded (recommended by others on here) to a 16mm triple wall poly. Probably going to use a Modine Effinity or Modine Hot Dawg heater but I’m not sure what size BTU, yet. Also, if a power outage Southern Burner used to make a very popular gas GH heater, but they went out of business. It required no electricity.
> I have many questions and greatly appreciate any input.


Consider a Hot Dawg heater with separated combustion. Most heaters use air from the structure for combustion - air you paid to heat and humidify. With separated combustion, air is drawn in from the outside through a pipe inside the exhaust flue, so it is preheated for greater efficiency - AND the interior atmosphere stays more stable.


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## ScientistKen (Feb 20, 2021)

I had a greenhouse back in the 90s that I built myself using treated 2x4's and 2x6's and corrugated fiberglass panels. North walls and bottom 4 ft of sides were insulated, which I recommend if you live in a cold climate. I ran heat ducts from my home furnace into drain pipe laterals (has big holes in the sides) that allowed mini air streams throughout greenhouse. 

It had many microclimates and it seemed pretty easy to figure out which plants wanted to be moved and where to. I think a greenhouse helps you gain intuition based insights about the orchids you grow. Snow would sometimes collect up to 6" thick even with my 45 degree angle, but I could step outside and tap slightly with my finger tips and it would all slide off immediately. I stapled plastic to the under sides of my rafters to reduce heat loss. One issue I had was that the wooden rafters got really hot and seemed to be almost burnt over time. I stained them for appearance but I think paining white would be better.


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## Duck Slipper (Feb 21, 2021)

awesomei said:


> My greenhouse is 12 X 20. I built it myself with 1/4 inch clear Twinwall panels over both sides of a 2x4 stud walls. My roof is 1/2 triple wall polycarbonate translucent. Already gotten too small!View attachment 25674


What size are your bench's? And tiered? Same on both sides? A 14’ house accommodates a center aisle bench, but the price increases quickly because of the engineering changes from 12’ to 14’...so I decided on 12’ width also.


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## PhragNewbie021 (Feb 21, 2021)

Very nice!


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## Phragper (Feb 21, 2021)

greenhouses are great. just never never big enough. Mine is 18 x 24 covered in double layer of plastic ( inflated) and shade cloth. use electric ceramic heaters in the winter with fans to aid in circulation. Summer is harder because hot air is just circulating. But it is my haven and every minute spent in it is my joy and passion


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## awesomei (Feb 21, 2021)

Duck Slipper said:


> Awesomei,
> What kind of heat are you using? Emergency heat?


Small electric heaters as needed. My GH seems well insulated, except in extreme cases or power failure. Then, I run a gasoline generator.


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## Ray (Feb 21, 2021)

I know you want to maximize bench space, but keep in mind that wide benches are difficult to reach across. Have you considered rolling benches? 

With a 12' wide structure, if you have three, 30" aisles, sides and center, you end up with two, 27" benches. With two, 30" aisles, you get three benches, two outside at 21" wide and a center one at 42". With a rolling bench setup, you could have one aisle and two, 57" benches, each accessible from both sides.


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## Linus_Cello (Feb 21, 2021)

A society member grower has rolling benches. Each section is divided in to 3, with the middle portion elevated, another consideration.


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## Duck Slipper (Feb 21, 2021)

Linus_Cello said:


> A society member grower has rolling benches. Each section is divided in to 3, with the middle portion elevated, another consideration.


I was actually thinking of rolling benches...later, when I started needing more space.


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## Duck Slipper (Feb 21, 2021)

Ray said:


> I know you want to maximize bench space, but keep in mind that wide benches are difficult to reach across. Have you considered rolling benches?
> 
> With a 12' wide structure, if you have three, 30" aisles, sides and center, you end up with two, 27" benches. With two, 30" aisles, you get three benches, two outside at 21" wide and a center one at 42". With a rolling bench setup, you could have one aisle and two, 57" benches, each accessible from both sides.


I’m actually drawing this out...rolling is probably what I will end up with. I can build the standard benches, tiered or otherwise. But the actual dimensions your giving...help. I’m sure when it is all done...I’ll say, the next one will be built like......


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## richgarrison (Feb 21, 2021)

Linus_Cello said:


> A society member grower has rolling benches. Each section is divided in to 3, with the middle portion elevated, another consideration.



Sam's benches are setup that way, with the center section high enough that the lower benches growing area isn't restricted at all.. plants in the middle are a stretch to reach... but the extra space is well worth it...


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## Duck Slipper (Feb 22, 2021)

With the initial cost of this GH, foundation, heat, fans, plumbing and electrical...initially, wooden benches constructed out of treated lumber are probably what I will start with. I’m certain I will outgrow it/fill it up and then go to rolling benches. 
While visiting Sam, I watched them in action. One surprising observation was the extreme narrowness of his aisles. Sam, entered an aisle and shuffled down each aisle sideways.


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## richgarrison (Feb 22, 2021)

Duck Slipper said:


> With the initial cost of this GH, foundation, heat, fans, plumbing and electrical...initially, wooden benches constructed out of treated lumber are probably what I will start with. I’m certain I will outgrow it/fill it up and then go to rolling benches.
> While visiting Sam, I watched them in action. One surprising observation was the extreme narrowness of his aisles. Sam, entered an aisle and shuffled down each aisle sideways.



yup its all about growing capacity versus cost... can't make any money off aisle space, and you still need to heat it.  the aisles at the orchid zone were very similarly sized.

i have another buddy locally that, as i was getting my first greenhouse setup, reminded me to leave some area to be able to sit out in the space and enjoy it... it's tough tradeoff... my greenhouse is 14 x 14 but 14' tall (as a lean to design) and i use all of the volume... and am glad it isn't bigger ... too many plants means either quitting my job and not having money to replace plants i kill or that turn out to suck, or having so many plants and too little time to care for them properly... at over 1k plants, this greenhouse happens to be the perfect size ;-) (cause it is what it is...) 

btw, my 'sit and enjoy it space' ended up being the stairs down from the door at the house...


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## monocotman (Feb 22, 2021)

Another option is to dig down and create a pit before installing your greenhouse. Have a look online for some ideas.
This is what quite a few old time greenhouses were like in the UK.
They are very thermally efficient, surrounded by all those earth walls.
David


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## LWP (Feb 22, 2021)

General bench 2 sided is 5 or 6 ft. . . . 5 ft. is easiest to work. Side benches 2.5 to 3 ft. wide. Height app 30 inch general up to 60 in high for highest on tiered benches. walkways 30 to 36 wide.


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## Duck Slipper (Feb 22, 2021)

Linus_Cello said:


> A society member grower has rolling benches. Each section is divided in to 3, with the middle portion elevated, another consideration.


3 rolling benches? Each with and elevated portion? Is it 12 ft. wide?


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## Linus_Cello (Feb 22, 2021)

Ray said:


> I know you want to maximize bench space, but keep in mind that wide benches are difficult to reach across. Have you considered rolling benches?
> 
> With a 12' wide structure, if you have three, 30" aisles, sides and center, you end up with two, 27" benches. With two, 30" aisles, you get three benches, two outside at 21" wide and a center one at 42". With a rolling bench setup, you could have one aisle and two, 57" benches, each accessible from both sides.





Duck Slipper said:


> 3 rolling benches? Each with and elevated portion? Is it 12 ft. wide?


I think each rolling bench is about 6 feet wide, so 2 foot sections


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## Duck Slipper (Feb 23, 2021)

Anyone have any experience with a Modine “Effinity” 93 heater compared to a Modine “Hot Dawg”? The Effinity is 93% efficient but considerably more expensive. The Hot Dawg claims 80% efficiency!


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## KeysGuy (Feb 25, 2021)

I had a 10x12 shed GH on south gable end of my house in NH before I retired and sold it.
Had an empire propane heater that worked well but OMG was it expensive. Even to just keep it at 55 degrees. which BTW was too cold for what I was trying to grow. The propane choice was made because it still runs when the power fails.


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## Ozpaph (Feb 26, 2021)

Duck Slipper said:


> While visiting Sam, I watched them in action. One surprising observation was the extreme narrowness of his aisles. Sam, entered an aisle and shuffled down each aisle sideways.


Sam is not that big - so he can negotiate the aisles easily


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## Ozpaph (Feb 26, 2021)

How do you make rolling benches? I assume the floor needs to concrete???


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## Ray (Feb 26, 2021)

Ozpaph said:


> How do you make rolling benches? I assume the floor needs to concrete???


No. The legs are stationary, but there are horizontal pipes that run laterally, and they need to be level. Then more "roller pipes" sit on those, running the length of the bench, with the bench top sitting on top of them.


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## Duck Slipper (Feb 26, 2021)

For those that haven't seen them before...for instance you would use two 5 foot wide rolling benches in a twelve foot house. The ability to roll each bench and have a two foot aisle on each side of each bench makes for excellent space utilization.


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## richgarrison (Feb 26, 2021)

Duck Slipper said:


> Anyone have any experience with a Modine “Effinity” 93 heater compared to a Modine “Hot Dawg”? The Effinity is 93% efficient but considerably more expensive. The Hot Dawg claims 80% efficiency!



Just to confuse the issue with more info... ;-) 

I heat my 14 x 14 x 14 with fin tube hydronic heat ... source is a propane hot water heater and the gadgetry for pumping the hot water through the tubes... farmtek (as well as probably some others) sells the gadgetry in a single pre built panel that you can plumb up to any hot water source of your desire... just thought i'd throw that out there as a solution...depending on your greenhouse setup, you could have all of that except for the actual fin tube in some adjacent structure... Mine is in my basement directly on the other side of the wall from my greenhouse.


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## Duck Slipper (Feb 27, 2021)

richgarrison said:


> Just to confuse the issue with more info... ;-)
> 
> I heat my 14 x 14 x 14 with fin tube hydronic heat ... source is a propane hot water heater and the gadgetry for pumping the hot water through the tubes... farmtek (as well as probably some others) sells the gadgetry in a single pre built panel that you can plumb up to any hot water source of your desire... just thought i'd throw that out there as a solution...depending on your greenhouse setup, you could have all of that except for the actual fin tube in some adjacent structure... Mine is in my basement directly on the other side of the wall from my greenhouse.


I have seriously considered floor heat, Pex tubing in the concrete, boiler or tankless heater.
It just is going to be considerably more expensive than a Effinity or Hot Dawg...Probably is the most efficient source of heat.


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## richgarrison (Feb 27, 2021)

you need a lot of floor to get enough heat via radiant... but that would certainly be comfy in the winter... ;-) the fin tube works great as its under the benches wrapping the external walls and the floor fans are naturally blowing the heat up under the root systems...


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## KateL (Feb 28, 2021)

Duck Slipper said:


> I have seriously considered floor heat, Pex tubing in the concrete, boiler or tankless heater.
> It just is going to be considerably more expensive than a Effinity or Hot Dawg...Probably is the most efficient source of heat.


Just wondering - why would you use PEX tubing, which does not transfer heat well, rather than copper, which does?


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## Duck Slipper (Feb 28, 2021)

KateL said:


> Just wondering - why would you use PEX tubing, which does not transfer heat well, rather than copper, which does?


There is lots of info on line about it and greenhouse supply companies sell the product specifically for floor heat...I called it PEX, actually called Tekcoil, looks like Pex. Much easier to use than copper.


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## KateL (Feb 28, 2021)

Thanks. I have a family member who might want to look into that.


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## PhragNewbie021 (Feb 28, 2021)

Can someone post pics of rolling benches for us novices?


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## Ozpaph (Feb 28, 2021)

copper needs to be 'insulated/covered/sealed' in concrete or it 'rots'.


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## Ray (Mar 1, 2021)

PhragNewbie021 said:


> Can someone post pics of rolling benches for us novices?


images.google.com


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## NYEric (Mar 1, 2021)

When I retire, nine years hopefully, I will look into this. Thanks for info all. BTW, Does someone make clear Quonset hut type structures?


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## PhragNewbie021 (Mar 1, 2021)

Ray said:


> images.google.com


Thanks Ray!


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## Duck Slipper (Mar 1, 2021)

NYEric said:


> When I retire, nine years hopefully, I will look into this. Thanks for info all. BTW, Does someone make clear Quonset hut type structures?


I’m retiring in two years hopefully!


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## cnycharles (Mar 1, 2021)

At work we have floor heat in concrete, and some of the houses have heat tubing directly under the bench tops, rubber tubes


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## paphiopere (Mar 2, 2021)

Estoy construyendo mi nuevo invernadero y he decidido instalar suelo radiante como un circuito más de la casa. La fuente de calorías es una aerotermia y el consumo se reducirá considerablemente con paneles solares. Voy a dar todos mis mimos a mis plantas. Incluso ha instalado una toma de agua para riego mixto para regar siempre con agua a 23ºC.


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## Ozpaph (Mar 3, 2021)

great pictures, unfortunately i cant read ?Spanish, i get the basic message. thanks


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## Ray (Mar 3, 2021)

Ozpaph said:


> great pictures, unfortunately i cant read ?Spanish, i get the basic message. thanks


Google translate can be your friend:

“I am building my new greenhouse and I have decided to install underfloor heating as one more circuit in the house. The source of calories is an aerothermal energy and consumption will be reduced considerably with solar panels. I'm going to give all my pampering to my plants. It has even installed a water intake for mixed irrigation to always irrigate with water at 23ºC.”


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## Ozpaph (Mar 4, 2021)

thanks. Like i guessed, mostly..........


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## Duck Slipper (Mar 4, 2021)

NYEric said:


> When I retire, nine years hopefully, I will look into this. Thanks for info all. BTW, Does someone make clear Quonset hut type structures?


 I looked for plans to build a GH...for some reason very hard to find. There are plans for smaller houses, but for a larger size such as a 14’x 30’ I couldn’t find them. You would think polycarbonate dealers would have some plans available but I couldn’t find them. But there is some info out there on Quonset type houses.


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## tomp (Mar 5, 2021)

Duck Slipper said:


> I looked for plans to build a GH...for some reason very hard to find. There are plans for smaller houses, but for a larger size such as a 14’x 30’ I couldn’t find them. You would think polycarbonate dealers would have some plans available but I couldn’t find them. But there is some info out there on Quonset type houses.


There is a handy book with the basic building details available in several formats: 
“How to build your own greenhouse” by Rodger Marshal. I just looked online and it appears to be ready available.


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## Duck Slipper (Mar 5, 2021)

tomp said:


> There is a handy book with the basic building details available in several formats:
> “How to build your own greenhouse” by Rodger Marshal. I just looked online and it appears to be ready available.
> View attachment 25973


I have the book, and some others...they are pretty basic, rudimentary plans. Myself and some friends are “Redneck” carpenters. We need more detailed plans. Perhaps even a materials list. Also it gets pretty sketchy on the attachment of Polycarbonate. Also, weight bearing engineering and design changes going from 12’ to 14’ and again to 16’ in width.


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## abax (Mar 5, 2021)

DS, we built our own rolling benches with treated wood and fencing wire and it's been extremely dependable and stable.
We've built all my benches and it's very easy. The metal benches tend to tip over and dump plants. John M. had
a bench catastrophe several years ago and it was a mess. He posted photos on another orchid forum when it
happened. We used 4x6 lumber just to be sure.


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## Ozpaph (Mar 6, 2021)

abax said:


> DS, we built our own rolling benches with treated wood and fencing wire and it's been extremely dependable and stable.
> We've built all my benches and it's very easy. The metal benches tend to tip over and dump plants. John M. had
> a bench catastrophe several years ago and it was a mess. He posted photos on another orchid forum when it
> happened. We used 4x6 lumber just to be sure.


Could you share some photos of the construction, please?


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## cnycharles (Mar 6, 2021)

Duck, check out charleys greenhouse supply. But I didn’t see any kits of 30’. Most likely getting larger is considered commercial type, and most would be having a greenhouse construction company design and build rather a home do it yourselfer. 
Polycarbonate safely installed most likely needs the specialized metal slotted framing instead of a homemade system of some kind.


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## Duck Slipper (Mar 6, 2021)

Exactly cnycharles. I contacted GH supply companies and none could supply a set of plans and materials lists for a given size. Even talked with a contractor and he had no luck. 
Example; Plans for a 14’ x 20’ polycarbonate and treated lumber GH...materials list for all the needed poly attachments, fittings, corner end pieces, etc. No such thing.


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## Ray (Mar 6, 2021)

I think you're just going to have to be a bit self-sufficient in that regard.

My 14' x 18' Turner Greenhouse had arches every 2' of length, with gussets at each intersection and a cross-brace between the opposite intersections of the wall and root panels. There were ties that ran the length of the structure, at the base, the eaves and the roof peak. the end panels of the sides and roof had diagonal braces for rigidity. The north end was wood and plywood, insulated with styrofoam, and the front had similar 2' spacing surrounding the door using the same steel angle used for the sides and roof.

When I bought it, it came with 28" wide acrylic panels that ran vertically, overlapping and attached to the arches using metal straps that were attached to the frame with bolts. I later replaced them with multiwall polycarbonate that was 48" wide. The channels that jointed the panels had a 1/2" gap in the middle that lined up with the frame, making them easy to attach with self-tapping screws that had rubber washers on them.


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## abax (Mar 7, 2021)

I'n sorry Ozpaph. I had photos on a computer that crashed without warning. I lost all those photos. We used 4x6 treated
lumber for the posts and 2x4 for underpining the wire. Then attached the "rollers" to the 2x6 posts. The hardest part
was stretching the fencing wire. I think we used the 2x4s every two feet under the wire on an 8' bench. We also built
three step benches for non-orchid plants, but I don't remember the details. We designed and built my 12'x28' greenhouse
20 years or more ago and I don't remember a lot of the details of construction.


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## ScientistKen (Mar 10, 2021)

What you run into with larger with wood framed greenhouses is that wider becomes more difficult to do with rafters. You might be better off with trusses after a point. 12 ft should be fine with rafters. With a longer greenhouse, you end up having potential issues with your ridge board. If not sufficiently supported it will want to sag. The big advantage for wooden greenhouses is they are easy to insulate and more DIY people are familiar with working with lumber as a building material.

The main issue I had was that my rafters got really hot. They appeared as if they were slightly burned over time. White paint might help with that.

The arch based greenhouses are designed to support the width and for length you just add more arches. I have never built that kind of greenhouse. I would expect them to be difficult to insulate and difficult to glaze if you are not using rolled plastic.


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## LWP (Mar 10, 2021)

Frame: 22 x 48 PT lumber. 14 ft center ridge, 10ft sidewalls. 4 x 4 posts for uprights on 10 ft centers. 2 x 6 x's roof rafters on 3 ft centers, 2 x 6 cross rafters on 10 ft centers, and wall framing on 2 ft centers. Built by myself with no outside assistance. 

Exterior: Sidewalls are 13cm double polycarbamate, roof inflated double poly, white 50%. Will remove top layer of white poly and replace with clear to improve lighting this spring. I can control light levels in summer with lite coats of 1 part white latex exterior white paint, diluted with 3 parts water, till I get the light levels right.

Heat: Two 120,000 BTU Modine propane heaters. This gives an operational heat capacity of 60 degrees night with 10 degree outside temp to maintain a night temp of min 55 degrees. I have the second heater as a backup in case the primary fails and it is set to fire at 50 degrees. I also have a generator should power fail, 4 - 36,000 BTU 'Kerosun' kerosene heaters and have irrigation foggers if all else fails.

Cooling: 4 ft x 22 ft x 4 inch Kool Cell pad recirculating evaporative system system. Exhaust fans are 30 inch, 2 stage attic exhaust fans rewired for reverse airflow and staged to operate in 5 degree intervals (80, 85, 90 and 95).

Greenhouse has run for 26 years with no structural issues in zone 7,


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## Ozpaph (Mar 10, 2021)

abax said:


> I'n sorry Ozpaph. I had photos on a computer that crashed without warning. I lost all those photos. We used 4x6 treated
> lumber for the posts and 2x4 for underpining the wire. Then attached the "rollers" to the 2x6 posts. The hardest part
> was stretching the fencing wire. I think we used the 2x4s every two feet under the wire on an 8' bench. We also built
> three step benches for non-orchid plants, but I don't remember the details. We designed and built my 12'x28' greenhouse
> 20 years or more ago and I don't remember a lot of the details of construction.


Thank-you for looking.


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## Duck Slipper (Mar 10, 2021)

Thanks for everyone’s input. Really do appreciate it!


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## awesomei (Mar 11, 2021)

Duck Slipper said:


> Awesomei,
> What kind of heat are you using? Emergency heat?


Elecrtic! switching to propane


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