I'm wondering about the etiquette of posting all the in text ads ... No. I know that they have nothing to do with you, goldenguy. GW must feel the need for them but the ads sure have become plentiful.

I think your mother-in-law is probably right. It looks like there will be adequate light for that shelf of plants. I'm not sure if there would be a great benefit from taking more of the exterior off, higher. Could you remove only the upper half of wall 3? Perhaps the interior shelf on the north wall could be moved to the south wall.

The depth of the shed will help moderate the temperatures, day and night.

No polycarbonate, just uv-resistant plastic film, but at 48o North & 2,000ft elevation, here is a picture of my sunshed on this GW thread.

I don't know what to say about your shed floor. This explains what I have been able to do without a floor, and what I'm doing again this winter, on this GW thread.

Now, you need local comments :o).

Steve

Thanks for the comments Steve I've followed your threads with great interest - your bok choi crops look especially inviting.

I can cut wall 3 partially and re-mount it. And I'm open to having plants on the ground, other shelves, or hanging. I wouldn't want to limit my options for plant placement in the future by leaving panel 1 shingled.

I suppose I'm going to have I learn myself over the years. But there's so much knowledge here it can't help to ask!

Goldenguy, I built a very similar greenhouse structure with the same N/Sorientation, same elevation, and an almost identical climate. In place of your wall 3 we have a 2 ft high base frame and a row of windows that crank open, and double-sided polycarbonate in a single plane for 2 and 3. Ours is somewhat larger, roughly 20 wide X 25 feet long. The north facing wall and ceiling is traditional stud/insulated/siding as are the east and west, the west has a 6 ft wide sliding glass door in the middle for western late afternoon sun.

so a couple of thoughts -

Double-thick poly carbonate will work just fine. You could also successfully build your own double-pane roof using clear polycarbonate sheets and just cutting them to size. Drill some small drain holes in the lowest and highest inside bits so they don't fog up

Your problem won't be keeping it warm, it will be keeping it cool enough during late-April and May and Sept-mid October. I combat this by opening up all my windows, and if I had it to do over again, I'd put in solar powered fan/vents in the roof. - they don't cost all that much.

I'm all about automation so if I can handle the cooling with a louvre vent and a powered or solar fan then I'm all for it. Thanks for the advice David.

I should mention that the western exposure abuts a large masonry retaining wall and is heavily shaded by mature trees from the afternoon sun that makes the rest of my backyard almost intolerably hot sometimes.

So if I was going to add any extra glazing it would have to be east facing but, I'm in the shadow of north table mountain so by the time the sun is high enough to catch the east wall it will be striking the south walls anyway.

The photo above was a false alarm since home despot sent the wrong panels. Nothing some complaining and a month can't fix.

Detail

Where the magic should happen once I figure all this out.

Any tips and suggestions are welcome. Thanks for looking!

Looking good, goldenz!

Thats looking really good, and you're going to be amazed at how much stuff you can grow in there.

I'm thinking those two vent caps you have for ventilation aren't going to cut it once summer rolls around. I'd look for something 10" dia, ideally with a solar powered fan. Just a real quick google, maybe something like this? solar powered vent that looks large enough

Your shed looks pretty air-tight. Depending on what you do over the winter, condensation might be an issue. Before winter, make sure you caulk with flexible caulking anywhere water may drip down. I ended up running folded bits of blue painters tape across the roof panels so the condensation would catch at the tape and drip to the floor instead of continuing on down to the walls.

Mine is hitting 95ºF these days. I need to put up the shade cloth pretty soon. Thats a pretty easy fix if your temps are hitting 110+

Edited to add: does this get sun most the day, or do those trees shade it a bit in the afternoon?

David ,

Thanks for the input. I'm very excited of course but am also suffering from some big time analysis paralysis about this project. Best to start slow I think.

The trees in the photo are to the west and do provide lots of shade in the afternoon, during the summer. They're not really in play during the winter due to the southern orientation of the sun.

I'm planning to install power ventilation, whether it's solar or wired I haven't decided yet. According to much literature I've read I need one air change per minute roughly which puts me at a 500-700CFM range, and in solar fans that's starting to get really expensive, especially if you consider that the rated output of solar fans is the maximum and not the average output.

You can see the tubes of silicon caulk on the bench, that's on the list of things to do, too.

Today I moved some pepper seedlings in there from under the lights, and I moved my WS containers in there too, thinking that the warmer temperatures might help them get started.

That sunshed is really coming together for you, Golden!

It sounds like you are working with some stats that should keep you on the right track. It has been about 20 years since the last and final expansion of my sunshed. I had advice from the local utility company engineers for the angle of the south wall and expected heating costs. I think that helped at least to encourage me.

I don't know if there was much out there for ideas on ventilation. I certainly learned how the sun could spike the temperature just as I learned how hours of darkness resulted in continuous heat loss, just not as quick!

My choice was a kitchen wall fan. I remember that I got the bigger of the two Lowe's had to offer ... wish it was a little bigger and had variable speeds. Cracking the door open moderates things fairly well. My 2 biggest problems are the quickness of the changes and frigid outdoor air. If it's 35° outdoors, you sure don't want lots of that air rushing in even if, or especially if, it's 95° in the greenhouse. Tricky! Air exchanges at all rates would sure be best but be prepared to prop something open or wedge something closed by less-than high-tech means.

Steve

Sounds like you're on the right track with the ventilation. When I was building mine, I asked/priced around and installed two, count 'em two, 2 ft dia ventilating fans in the north wall, hard-wired to a separate thermostat starters. So the season starts, I set the fans to turn on at 90º, and one night shut the door that connects the greenhouse to the garage, isolating the room. Next morning the sun comes up, room gets hot enough the fans turn on. The suction was so great, up came about 10 gallons of muddy sludge out of the floor drain pipe. Another time they kicked on when the windows were open but the doors closed - half the screens blew in. :) I haven't used them for a few years. If I had it to do over, I'd put in automatic roof vents and a swamp cooler.

I built a wood frame "sunshed" 10x16 nine years ago. A couple of things learned, as mine is now comfortable enough to use as living area even in the depths of winter.

Insulation: use as much as you can without breaking the bank. Stud cavities, roof bays.... I merely used painted OSB on the inside of the studs creating an insulating void. I'm zone 8, but I can keep 40 over ambient without getting a letter of appreciation from the local electric utility. I'd insulate the walls first if'n I was to do it again. Getting ready to insulate the roof as I do some painting.

Ventilation: Yeah, it's critical. Bought a 14" exhaust fan with hard-wired, opening lovers for the intake at the other end. Still gets bloody hot, even with shade cloth. Wrap it around 4" PVC pipe so you can use pulleys and cord to roll it up or down like an external window shade.

Thermal mass: here again, more is better. Mine has patio blocks on several tons of gravel. Anything that will hold water should be positioned so these can soak up heat during the day. Kitty litter containers are free and quite useful. Plywood can't store any warmth.

Just came back in from the "conservatory". This winter, I installed two, twin 48" long T-5 fixtures in the dark back corner. Ordinarily, the coffee trees would just drop half their leaves and sulk. The coffee trees are in their second bloom - even more prolific than the one three weeks ago.

Cheers

Hey guys, been a while.

So this is where everyone is chatting on the greenhouses. Since DH still has not built mine (materials have been here four years now, but he doesn't want to dig the hole) I have been looking at other options.

I'm in Yoder CO, for those of you who don't already know. Which means I am almost on the Arkansas banana belt but I also register -24 some winter days. We also get high winds which means anything with shingles is probably not going to survive. And if it is not anchored in twenty different places, it will be effectively relocated with the next good windstorm.

So, as I was saying, DH hasn't build my greenhouse yet and I am getting really impatient. Started looking at different order kits. I received information for Simply Solar Greenhouses. Anyone done any research on this or have one? They claim it holds up to wind and is self ventilating. It comes as a one piece unit that they install where you tell them. I wouldn't have to do it or wait on DH. It sounds too good to be true, which as we all know, usually means that it is. So far, the only thing I found was their delivery fee for me is another $950 on top of the unit price. Simply Solar Greenhouses

Also looking at fixing a few things on my barn (shingle roof that is mostly gone to metal and fixing the south wall. Thinking it might serve as a partial greenhouse, however none of the walls are insulated. They have 7/16 OSB and 7/16 8OC siding all the way around (Okay, busted, on three sides, the south wall is getting done this summer and windows are being added there.). Most of the interior walls have 1/4 plywood, but no insulation. Should I consider putting blow in insulation in there? A little concerned that the livestock might get into it which is why I did not go to the expense to begin with.

Also planning on adding a few cold frames with slider doors that I have saved. Anyone found good plans for that?

Thanks all. Glad to see so many familiar faces still here. I miss having time to hand out.

Billie

All: thanks for all the helpful suggestions and tips. I've installed about 2/3 of the R-13 insulation boards and a power vent roof fan now along with some intake louvre vents.

I was spurred to action last Friday when I neglected to open the greenhouse doors and the temperature reached 125f killing my cole crop seedlings and probably some others that were just thinking about germinating.

Now with some passive ventilation the temperature only hit 92 on a glorious sunny day today.

Billie: Id take that 950 delivery charge and hire an excavator to dig and shore your greenhouse pit. Having an earth shielded structure will address many of your insulation concerns. Also DH won't have any excuse left.

Progress

Golden, want to thank you for your comment. My DH apparently does not speak garden and did not understand what I was saying until I read him your comment. Now he gets it.