Hello, I am extremely new to this. My wife and I started a garden last year at random as the quality of produce here is ragged, especially at big box stores that leave items to rot in the boxes for sometimes weeks. regardless of this we expanded massively this year and germinated roughly 127 plants. We quickly found out how much more space we need to do this properly as we also purchased a 4x4 grow tent to germinate in which was difficult nailing down humidity and ventilation coupled with lighting. I would like to build an even span style out of wood which will provide its own challenges. I'd like to do metal corrugation possibly around the bottom or possibly 2x6's. I was thinking of doing shelving as well to allow bigger plants to flourish in a smaller space so I can divide things up and also have storage in the rear. I currently live outside of Pueblo, Colorado. We are mountain desert here so nothing like the rest although we have heavy heavy winds with cold fronts. we also sit at about 4400' elevation and would like to grow in it year round. My questions are these.

1. Does anyone have have experience using the polycarbonate double wall or know of good sites with good videos showing installation for an even span a 10'x 20' greenhouse ?

2. Does anyone have good heating and cooling ideas I could look into? It'll be next to the house but be a while before I can get electrical to it so i figured solar ventilation would help but also maybe pop up vents in the roof too to catch the normal eastern to western winds

3. What kind of base works best for most greenhouses? we have very heavy dense clay here so sometimes we tend to look down on rock due to picking up mud and tracking although that could be avoided with simple practice as well as layout of the greenhouse right next to the home.

Thank you for all your help!!
Tim

I live at 5000 feet in Reno, NV at the west edge of the Great Basin. We have very little snow or rain but do have wind, regularly over 50 mph, winter temperatures approaching 0 and summer highs near 100. My greenhouse is 5-wall super polycarbonate because of the wind and because I am growing mostly orchids.

My daughter has a twin-wall polycarbonate greenhouse but she does not try to keep it above freezing in winter and it is a little more protected from the wind. Check to see if twin-wall will withstand the winds in your area. I assume you will be using your greenhouse seasonally? Or are you growing in winter also?

No matter what, you will need some kind of heat. Daughter uses a small milk barn heater and it seems to work well but her GH is about half the size you are planning. The temperatures inside her GH do drop below freezing (upper 20's) but she is growing plants that can withstand the cold. There have been quite a few discussions on this Forum about propane heating. That may work for you but it must be installed and vented properly for your safety but also for your GH's. Kaboom!

I don't worry about summer heat. If you are building your own plan though, the more vents and doors, the better. I leave the door open all summer and have automatic roof and side vents built into the GH walls and roof. You can cool a GH down dramatically by adding a mister and covering the roof with shade cloth (I have both). If you decide to get a shade cloth, add some sort of support to hold it off the roof. Mine stays up all year round but I'm not worried about snow. The hardest part of shade cloth is getting it up there and down again. When I did remove it annually (old GH), I often though how handy it would be if the top of the GH had coyote bars on it.

Swamp coolers are popular for GH cooling. I did try that but decided it was more of a hassle then I wanted to deal with and it took up a lot of space.

The wind is a big factor. My greenhouse is engineered for 130 mph winds - its got steel I-beams as added support. If you are building a wooden frame, I would follow the local building code because it is designed for your local weather. In my area, that would be studs on 16" centers but as the walls in a house are part of the structure, you may need additional support. Don't forget the shear - in a regular building, that is the outside layer of plywood over the entire frame. Polycarbonate isn't going to provide a lot of shear.

Do you have a snow load? Luckily, we don't. But the more snow, the steeper the pitch in the roof. You want it to slide off, not fall through.

I would forget the metal corrugation around the bottom and instead put in a concrete stem wall and foundation to bolt the whole thing down to, just like attaching a house to a foundation. My stem wall is 12 inches high and the foundation is 18 inches deep - below the freeze depth. The floor of my GH is also concrete but sand and brick (like a patio) is also a good solution. You definitely want a floor. And drains. Build drains into the bottom of the stem wall. Add water pipes and faucets and electrical outlets as you build.

The best shelving is wire - that way the plants on the bottom get light from the top. My lowest plants are at the height of the stem wall, except for some large pots sitting on the floor. I use Closetmaid wire pantry shelves. One side is held up by hooks in the studs and other is held by chains and hooks from the ceiling. They come in 12, 16 and 20 inch widths and can be cut to size with bold cutters. As your plan is for a 10 ft wide GH, think about how wide the isles need to be and build something down the center. I had a wide GH at my old house; I used wire Baker's Shelves and hung things from the ceiling. This time around, I built a 6 ft wide GH so 16" shelves on either side and still over 3 ft down the middle.

Last summer, I added an automatic watering system on timers as I'm not good at remembering to water. The sprinklers are mounted on the ceiling and the water is able to get to all the plants on all the levels because of the wire shelves. It needs to run for only 2 minutes to thoroughly water everything.

Oh, polycarbonate sheeting... The edges need to be sealed somehow. On my GH, they are taped on the edges and held in place by metal frames but the entire GH is metal. I'm not sure what you would do with a wood structure but definitely something to look in to as something needs to hold the panels in place. If you don't seal the edges, the panels fill up with moisture (and bugs) and become opaque and gross.

Did I cover everything?

DaisyI said:I live at 5000 feet in Reno, NV at the west edge of the Great Basin. We have very little snow or rain but do have wind, regularly over 50 mph, winter temperatures approaching 0 and summer highs near 100. My greenhouse is 5-wall super polycarbonate because of the wind and because I am growing mostly orchids.

My daughter has a twin-wall polycarbonate greenhouse but she does not try to keep it above freezing in winter and it is a little more protected from the wind. Check to see if twin-wall will withstand the winds in your area. I assume you will be using your greenhouse seasonally? Or are you growing in winter also?

No matter what, you will need some kind of heat. Daughter uses a small milk barn heater and it seems to work well but her GH is about half the size you are planning. The temperatures inside her GH do drop below freezing (upper 20's) but she is growing plants that can withstand the cold. There have been quite a few discussions on this Forum about propane heating. That may work for you but it must be installed and vented properly for your safety but also for your GH's. Kaboom!

I don't worry about summer heat. If you are building your own plan though, the more vents and doors, the better. I leave the door open all summer and have automatic roof and side vents built into the GH walls and roof. You can cool a GH down dramatically by adding a mister and covering the roof with shade cloth (I have both). If you decide to get a shade cloth, add some sort of support to hold it off the roof. Mine stays up all year round but I'm not worried about snow. The hardest part of shade cloth is getting it up there and down again. When I did remove it annually (old GH), I often though how handy it would be if the top of the GH had coyote bars on it.

Swamp coolers are popular for GH cooling. I did try that but decided it was more of a hassle then I wanted to deal with and it took up a lot of space.

The wind is a big factor. My greenhouse is engineered for 130 mph winds - its got steel I-beams as added support. If you are building a wooden frame, I would follow the local building code because it is designed for your local weather. In my area, that would be studs on 16" centers but as the walls in a house are part of the structure, you may need additional support. Don't forget the shear - in a regular building, that is the outside layer of plywood over the entire frame. Polycarbonate isn't going to provide a lot of shear.

Do you have a snow load? Luckily, we don't. But the more snow, the steeper the pitch in the roof. You want it to slide off, not fall through.

I would forget the metal corrugation around the bottom and instead put in a concrete stem wall and foundation to bolt the whole thing down to, just like attaching a house to a foundation. My stem wall is 12 inches high and the foundation is 18 inches deep - below the freeze depth. The floor of my GH is also concrete but sand and brick (like a patio) is also a good solution. You definitely want a floor. And drains. Build drains into the bottom of the stem wall. Add water pipes and faucets and electrical outlets as you build.

The best shelving is wire - that way the plants on the bottom get light from the top. My lowest plants are at the height of the stem wall, except for some large pots sitting on the floor. I use Closetmaid wire pantry shelves. One side is held up by hooks in the studs and other is held by chains and hooks from the ceiling. They come in 12, 16 and 20 inch widths and can be cut to size with bold cutters. As your plan is for a 10 ft wide GH, think about how wide the isles need to be and build something down the center. I had a wide GH at my old house; I used wire Baker's Shelves and hung things from the ceiling. This time around, I built a 6 ft wide GH so 16" shelves on either side and still over 3 ft down the middle.

Last summer, I added an automatic watering system on timers as I'm not good at remembering to water. The sprinklers are mounted on the ceiling and the water is able to get to all the plants on all the levels because of the wire shelves. It needs to run for only 2 minutes to thoroughly water everything.

Oh, polycarbonate sheeting... The edges need to be sealed somehow. On my GH, they are taped on the edges and held in place by metal frames but the entire GH is metal. I'm not sure what you would do with a wood structure but definitely something to look in to as something needs to hold the panels in place. If you don't seal the edges, the panels fill up with moisture (and bugs) and become opaque and gross.

Did I cover everything?

Just wow haha. I wasn't expecting this at all. I will be doing a wood frame greenhouse for sure so I will just incorporate vents and all that into mine. I haven't started planning the building itself yet however, we will be following international Building codes. As far as the shear, Should I plywood all sides like that and just leave the roof as polycarbonate then? I'm kind of confused on that part. on the panels my idea was also to tape the edges of the panels. I do want to use mine year round although we are going to try to divide the greenhouse into 3 sections. 1 for germination, 1 for a colder zone and then another section for storage possibly. Each section will more than likely be individually heated via propane temporarily. We do have snow load that varies by elevation. As far as wind load we have a required 115mph at 3 sec burst requirement. As far as the concrete I may have to have someone come do that then because our frost line is 44" up here. we on our property have bedrock at between 8' and 15' I was planning on wire for shelving as I get going solely due to drainage and low replacement over the life. we were going to do the shelving at 3 foot wide on each side to leave about 4' of room down the middle to the back where another door will be. I wasn't too worried about snow load though as we are planning on doing a 60 degree slope roof. It won't be a traditional ridgebeam/ridgeboard design though. We are planning on overlapping one side of the roof so we can do vents along the entire ridge. I was planning on doing 16 oc with 2x4 for walls or 22" OC with 2x6 for walls depending on the polycarbonate needed for the sides with insulation

The diagonal strip of metal behind the plants is a shear strap. It is a thin metal piece that spans two 2-ft wide panels from the bottom to the top of the wall.



I thought about dividing my greenhouse but (luckily) decided against it. The invisible line between cactus and orchids has moved more than once.

Take a look at this thread. Some photos and specs on my greenhouse, at 8000 ft.in the Rockies, very cold winters. Also several other interesting setups.

The thread "Please share photos of your greenhouse" in Greenhouses forum

That's a nice greenhouse, Chip. Who is the manufacturer?

More importantly, you can see two shear straps in the first photo.

DaisyI said:I live at 5000 feet in Reno, NV at the west edge of the Great Basin. We have very little snow or rain but do have wind, regularly over 50 mph, winter temperatures approaching 0 and summer highs near 100. My greenhouse is 5-wall super polycarbonate because of the wind and because I am growing mostly orchids.

My daughter has a twin-wall polycarbonate greenhouse but she does not try to keep it above freezing in winter and it is a little more protected from the wind. Check to see if twin-wall will withstand the winds in your area. I assume you will be using your greenhouse seasonally? Or are you growing in winter also?

No matter what, you will need some kind of heat. Daughter uses a small milk barn heater and it seems to work well but her GH is about half the size you are planning. The temperatures inside her GH do drop below freezing (upper 20's) but she is growing plants that can withstand the cold. There have been quite a few discussions on this Forum about propane heating. That may work for you but it must be installed and vented properly for your safety but also for your GH's. Kaboom!

I don't worry about summer heat. If you are building your own plan though, the more vents and doors, the better. I leave the door open all summer and have automatic roof and side vents built into the GH walls and roof. You can cool a GH down dramatically by adding a mister and covering the roof with shade cloth (I have both). If you decide to get a shade cloth, add some sort of support to hold it off the roof. Mine stays up all year round but I'm not worried about snow. The hardest part of shade cloth is getting it up there and down again. When I did remove it annually (old GH), I often though how handy it would be if the top of the GH had coyote bars on it.

Swamp coolers are popular for GH cooling. I did try that but decided it was more of a hassle then I wanted to deal with and it took up a lot of space.

The wind is a big factor. My greenhouse is engineered for 130 mph winds - its got steel I-beams as added support. If you are building a wooden frame, I would follow the local building code because it is designed for your local weather. In my area, that would be studs on 16" centers but as the walls in a house are part of the structure, you may need additional support. Don't forget the shear - in a regular building, that is the outside layer of plywood over the entire frame. Polycarbonate isn't going to provide a lot of shear.

Do you have a snow load? Luckily, we don't. But the more snow, the steeper the pitch in the roof. You want it to slide off, not fall through.

I would forget the metal corrugation around the bottom and instead put in a concrete stem wall and foundation to bolt the whole thing down to, just like attaching a house to a foundation. My stem wall is 12 inches high and the foundation is 18 inches deep - below the freeze depth. The floor of my GH is also concrete but sand and brick (like a patio) is also a good solution. You definitely want a floor. And drains. Build drains into the bottom of the stem wall. Add water pipes and faucets and electrical outlets as you build.

The best shelving is wire - that way the plants on the bottom get light from the top. My lowest plants are at the height of the stem wall, except for some large pots sitting on the floor. I use Closetmaid wire pantry shelves. One side is held up by hooks in the studs and other is held by chains and hooks from the ceiling. They come in 12, 16 and 20 inch widths and can be cut to size with bold cutters. As your plan is for a 10 ft wide GH, think about how wide the isles need to be and build something down the center. I had a wide GH at my old house; I used wire Baker's Shelves and hung things from the ceiling. This time around, I built a 6 ft wide GH so 16" shelves on either side and still over 3 ft down the middle.

Last summer, I added an automatic watering system on timers as I'm not good at remembering to water. The sprinklers are mounted on the ceiling and the water is able to get to all the plants on all the levels because of the wire shelves. It needs to run for only 2 minutes to thoroughly water everything.

Oh, polycarbonate sheeting... The edges need to be sealed somehow. On my GH, they are taped on the edges and held in place by metal frames but the entire GH is metal. I'm not sure what you would do with a wood structure but definitely something to look in to as something needs to hold the panels in place. If you don't seal the edges, the panels fill up with moisture (and bugs) and become opaque and gross.

Did I cover everything?

Just wow haha. I wasn't expecting this at all. I will be doing a wood frame greenhouse for sure so I will just incorporate vents and all that into mine. I haven't started planning the building itself yet however, we will be following international Building codes. As far as the shear, Should I plywood all sides like that and just leave the roof as polycarbonate then? I'm kind of confused on that part. on the panels my idea was also to tape the edges of the panels. I do want to use mine year round although we are going to try to divide the greenhouse into 3 sections. 1 for germination, 1 for a colder zone and then another section for storage possibly. Each section will more than likely be individually heated via propane temporarily. We do have snow load that varies by elevation. As far as wind load we have a required 115mph at 3 sec burst requirement. As far as the concrete I may have to have someone come do that then because our frost line is 44" up here. we on our property have bedrock at between 8' and 15' I was planning on wire for shelving as I get going solely due to drainage and low replacement over the life. we were going to do the shelving at 3 foot wide on each side to leave about 4' of room down the middle to the back where another door will be. I wasn't too worried about snow load though as we are planning on doing a 60 degree slope roof. It won't be a traditional ridgebeam/ridgeboard design though. We are planning on overlapping one side of the roof so we can do vents along the entire ridge. I was planning on doing 16 oc with 2x4 for walls or 22" OC with 2x6 for walls depending on the polycarbonate needed for the sides with insulation

DaisyI said:The diagonal strip of metal behind the plants is a shear strap. It is a thin metal piece that spans two 2-ft wide panels from the bottom to the top of the wall.



I thought about dividing my greenhouse but (luckily) decided against it. The invisible line between cactus and orchids has moved more than once.

Ah ok, yes. The design I am looking to build does include those tied into the exterior wall via cuts with an oscillating tool. I was deciding whether or not to cut into the wall stud like that to do so or figure something else out

subarctic said:Take a look at this thread. Some photos and specs on my greenhouse, at 8000 ft.in the Rockies, very cold winters. Also several other interesting setups.

The thread "Please share photos of your greenhouse" in Greenhouses forum

The one I am planning on building actually is very similar to yours in wood construction as well (yours appears to be wood haha) Your pictures are amazing as well. Would you mind if I picked your brain on a few things as well? How high of winds do you get up there where you are in Wyoming? We routinely have roofing tiles come off during the spring it gets that bad here. It's really only bad when the storms come in in the spring and winter. Other than that it stays beautiful. We will definitely be much bigger on ours. Ours will not be attached to the house either. We want some additional storage as well for the lawn mower, weed eater, tiller, hand tools, hoses, etc.. all said and done though our actual size may encompass what you have roughly.

MoonShadows said:That's a nice greenhouse, Chip. Who is the manufacturer?

I designed it for the local climate and built it in 2009 with help from a carpenter pal, using some lumber from a shed I tore down to clear the spot. The roof is 6-wall poly and the sides are 3-wall. The foundation is foam insulated about 3 ft. deep, rammed sand with PEX tubing to diffuse heat from the flat-plate solar collector.

It was a lot of work, but that's what it takes to grow tomatoes all winter in our savage local climate.

subarctic said:

I designed it for the local climate and built it in 2009 with help from a carpenter pal, using some lumber from a shed I tore down to clear the spot. The roof is 6-wall poly and the sides are 3-wall. The foundation is foam insulated about 3 ft. deep, rammed sand with PEX tubing to diffuse heat from the flat-plate solar collector.

It was a lot of work, but that's what it takes to grow tomatoes all winter in our savage local climate.

Fantastic!