BC or Charlie's Solar Gro GreenHouse

Hi gang,
I know their expensive but this would be a gift to my wife from our sons... Pretty good kids...
Well, My wife used to work in a Commercial GH up the street & found it the most relaxing & enjoyable work she ever did. For some reason my wife has always loved these particular BC Greenhouse or under Charlie's Solargro, San Juan ,greenhouse name.
Maybe because her sister lives in B.C., Vancouver, but anyway this has always been the one.
We could never afford such a thing but the boys got together & ordered one up for her.& me too I guess.
Don't think she'll kick me out of it if I build it???

Is this GH as good as it's price ?
Any experiences with the beast?

Sorry to bother you guys.

I Thank you
I Thank my boys &
I Thank God.

Good luck in all your growing projects.
Paul

No bother, Keywest, your GH adventure is just beginning...!

Which model? What glazing?

Don't forget step number one...decide what you (your wife) will use the GH for...seed starting from March to May is totally different that keeping mangos and bananas.

Hello all,

Stressbaby, Thanks so much for jumping in... I would like to talk about it if it's ok??

The model the boys picked out is 8 x 14, actually about 6" longer & wider.
It's frame is aluminum & has 6 mm Poly carbonate sides & roof with an 8.5/12 roof pitch with 5'6" sidewalls.
Comes w/ (2), 2x4' roof vents, & a regular aluminum front and a back door, w/ screens.

I have to build a foundation because the ground slopes away to about 18" where my wife wants it.
I''m thinking of sauna tubes for anchoring. and cement blocks in between the tubes to hold the dirt inside.
Then because of you guys and your Great ideas I will try to place foam insulation under & around the outside.

Thankyou all for bieng here to read all the great information that would take years to learn on my own.

I don't know much else about it except it would not be coming if the were not for the boys.
Both my wife & I are really excited about this new baby for the yard.

We always have flowers & a big vegetable garden & love the outside so maybe we can learn to grow a lot from seed, I hope.

Anyway thanks for listening & whatever you say I'll pay close attention to.

Thanks, Paul & Carol

Stressbaby,

I forgot to say what we would like to do in the GH.......... (We are in Zone 6)
We would love to have it hot all year to grow everything but we won't be able to afford such a fantasy.

We are hoping that we can have it at least warm enough to overwinter some Tropical's we have & maybe grow some cool weather stuff in the freezing cold weather. Maybe in March or so we can get it warm enough to start some seeds & things. We really hope so....If not we can still start them in the house first but I really hope not.
I plan to follow advice about all the ways of winter insulation I've read about.....(Really Insulate it Well)!!!

We have No Idea how well ventillated it will be in warmer weather & what to do about that or heat & stuff.
It does have 2 doors & 2 big roof vents, will that be enough W/ a portable fan?, Maybe?

There is so much to learn about. She worked in a greenhouse but never ran one & everything is sooooo different BUT exciting & a challenge.

Thanks again, Paul

Paul, can I ask you a couple of questions?

Do you plan to run electricity to the GH? Any thoughts on how you will heat it? And does the slope go off to the south or another direction? "I'm thinking of sauna tubes for anchoring. and cement blocks in between the tubes to hold the dirt inside." Sorry, I'm not following you there.

Here are my thoughts so far: read up, starting with The Greenhouse Gardener's Companion and the links in the sticky thread at the top.

Fully insulate the north wall and the north end of the roof. At least 50% of your heat will be lost through the roof and the north roof doesn't let any light through in the winter anyway. Use a foil-backed foamboard to reflect the light/heat off the north wall and back into the greenhouse.

Don't bother insulating under the floor; instead, insulate the perimeter. As Stosh said in another thread (better than I did) the ground underneath you isn't that cold. It is the ground laterally that gets cold. Insulate with vertical foamboard around the perimeter of the foundation.

Consider two types of fans, HAF and exhaust. Horizontal Air Flow fans move the air around the GH and are sized at cfm = at least 2 times the floor area. Exhaust fan (which I think you'll need if you want to use the GH in the summer at all) pulls air out of the GH and is sized at cfm = volume of the GH in cubic feet. A portable box fan might do the job there, depending on placement.

Paul,
I'll just add a little to SBs great recommendations.
I have a 9x16 greenhouse attached to my house and I use it all year. You're right about the crazy heating bills in the winter. If you just keep it above freezing for "survival only" of tropicals, then it won't be quite as bad. This is where heat storage is VERY important to lower your bills. Huge barrels of water, a heat storing floor (not insulated), etc. Also very important is how airtight it is. Windy, cold days (like we had for the last 1.5 weeks) can just kill any heat inside if it leaks.
Like SB said, you'll need to think about your heating because that's got to be one of the biggest considerations. You should plan on running electric to the greenhouse no matter your heat type. Also the fans are very important. I never knew the suggested CFMs like SB said. I just know that you've got to feel a breeze everywhere inside and run the fans intermittently at least 10 min per hour if not 20. My first winter I lost a lot of palms because I didn't have the airflow. They molded, rotted, mildewed, etc., then died!
As far as exhaust fans, if you only have 2 roof vents then you definitely need an exhaust fan. If you keep both front and back doors open, it's iffy. If you have vents on the knee wall along with vents on the roof, then you'll be OK as long as you leave the doors open. Top and bottom vents work pretty well with doors especially in the northeast. We almost never have the 100 degree days that a lot of the rest of the country can have.

I think I know what you mean about the foundation. I always called them "sono" tubes, but maybe you're right. They are just heavy duty cardboard tubes that you fill with concrete, right? That sounds like it would work great, but it might be a little overkill. Many people anchor a greenhouse to the ground by using dirt anchors. I don't know what the correct name is, but they're like heavy duty spirals that you spin into the ground and then fasten to a corner of the greenhouse. Also, many just lay down pressure treated or synthetic lumber as the base. Yours will definitely be stronger. Maybe you're using the block not only as a foundation, but also as a knee wall? One thing nice about the block is that it will allow you to easily install foam board to insulate laterally before you fill with dirt. Again, don't bother insulating underneath. If you really want to go crazy with heat storage, I think it was DigitalDave that once said we should stop treating the ground as our enemy. You could run water pipes in the ground to heat the ground during the day so at night it would radiate back up into the greenhouse. Not much of the heat would be wasted because you'd be insulated laterally. You'd have the perfect setup to do it because you need to fill with dirt anyway. None of us ever want to do it because we're not adding dirt, just leveling the site. The pipe above ground would have to go to some kind of heat collector, like black pipes, large heat sinks to take heat from the air, etc. This might be getting a little crazy for you, but we're all crazy.

At least I am.

Stosh

Hello again,

It sure feels good to talk with the Pros....
Stressbaby and Stosh507,
I will put Electricity and water in.. My water supply freees in winter & must be drained but ok for most of the year.
The GH will face South with the ends E & W. I have been reading T G.H. gardeners Companion Because I saw it spoken of highly on this Board.
The Co. sent me the schematic of the GH so I could get the foundation ready.
I tried to upload the picture along with one of the "sono" tubes in the ground as well.
You are right in that they are cardboard tubes filled w/ concrete. I was wrong in my spelling. In between the cement tubes I have to put something to hold the dirt inside so I could only think of cement blocks due to the weight of the dirt & they won't rot. Their not relly for support just a barrier .
I will insulate the outside perimeter and maybe not underneath.
They are sending me a small fan just to move the inside air.
I would like to have an inside slightly raised planting bed on the south.wall, a brick walkway ( I have a lot of old bricks), in the middle & stones on the North.floor which will be where all the storage plants will go.
As far as the underground water/heating pipes go, I really open to the idea but confused. Do I use a small pump & store the water in black drums? Is that the idea?

Thanks ever so much I'm ahving fun already.
As far as heat, I'm not sureprobably start w/ electric. .


thanks, Paul

Here is a picture of the 1'st Sono tube in place.
This is the location of the Greenhouse, I will move the fence to fit the GH sides.
This is why we have 2 doors. 1 in the enclosed area the other to exit into back yard.
There is an 18" difference between the front near fence and rear.
This is also looking East.

Paul

Paul,
Electric heat is fine, but make sure you run enough electric. In my opinion you'll need 220V run with at least 10 ga wire, preferably 8 ga. Size the breaker according to this main wire to the GH. Then you'll need a sub panel in the greenhouse for 110V and 220V lines. Just for comparison, I heat my 9x16 GH with electric also. I have a 5000W heater which draws nearly 21 amps at 220V. This heater is perfect for my greenhouse. I keep it approx. 70 degrees all year and when it gets really cold (below 10) it can't quite keep up. It's even worse when it's really windy. All electric heat is the same, so don't spend money on so called "efficient" models. That's all BS. There is no such thing. Every heater puts out exactly the same amount of heat per watt used. Most "over the counter" heaters max out at 1500W because they run on 110V. So if you wanted 3000W you'd just buy 2 heaters, right? Not so fast. Each heater would require its own 14 ga dedicated wire and circuit SEPARATE from any other lines. This is actually more work. You could also run a single very heavy duty wire, but the wire would have to be heaver than the 220V solution because 2 1500W heaters would draw 25 amps at 110V versus 21 amps at 220V. That's the magic of 220V - much more watts (and therefore heat) from a smaller wire.

Since our greenhouses are similar in size - I'll go out on a limb and guess how well a 1500W heater would work. If my 5000W heater can keep my greenhouse 60 degrees above ambient, then a 1500W heater would go about 18 degrees above ambient. I'm not sure if it's this easy or not, but certainly an educated guess. There are probably some crazy complicated temp curves when it comes to heating, not to mention you may build your GH much more airtight and/or with better materials, but this is close enough. Since you are zone 6, temps can fall below 0 each winter. That means that with 1500W heating your GH, it may fall below 20 inside. You decide if that's acceptable.

I'm still a little confused about the block wall. Are you not going to back fill? So this greenhouse will be above grade? If so, then you must be using the blocks as a retaining wall. If you are above grade, then it's EXTRA important to insulate laterally since the block will be exposed to the elements.

I'm not sure anyone has ever done the "ground as heat storage idea", but if you were going to try it, it would go something like this: Underground you would snake some kind of floor heating flexible pipe, like they use in houses. You would snake it back and forth many many times pretty close to each other and this would heat the ground near and/or above it. This underground pipe would be attached to different pipes above ground. These pipes would have to somehow collect the heat from the sun. They make solar panels specifically for heating your pool that are already plumbed. You just have to hook it up to your system. Or you could design your own. This system could be outside or inside your GH, depending on how much room you have. Then comes the more complicated part - now you have to circulate the water ONLY when the water in your solar collector is hotter than the ground temp under the GH. Another way that isn't quite as efficient, but would probably work, is when the sun is out, circulate the water. Now an obvious problem comes up - at night when it's cold and the sun isn't out, what will happen to my solar collector pipes? They will break! Sorry, but that's pretty funny. I don't have an easy solution for that right now, but you could use some kind of drain-back valve that would connect to a holding tank to store the extra water when not in use. Woah! This is getting crazy!

I'm pretty sure all the extra work, materials, and design isn't worth it or it would be happening everywhere. You're one step ahead because you don't have to excavate under the GH because you're filling in with dirt anyway. If you happened to have lots of extra flex pipe laying around, or access to it cheaply, it also might pay. But at this point you'd be the guinea pig.

If you don't want to go through all that, then yes, the black drums are excellent as a buffer, but unfortunately they really only make a difference during the first few hours after the GH starts cooling down. The problem is that to get enough heat capacity from water (or any other material), you need a LOT of it - like an entire wall filled with water, not just a few jugs or barrels. Somebody needs to invent a phase change material that operates in the 50-70 degree range that doesn't cost a fortune. Water works great for this, but it works at 32 degrees which isn't ideal.

One quick tangent - I use water as a phase change material inside a mini greenhouse that protects a windmill palm that I have planted outside. These windmill palms don't mind 20 degrees and can handle 5-10 degrees briefly. Obviously, that's not hardy enough for our zone 6, but when I stack water jugs all around it and build a mini enclosure around it, it does pretty well. When the temps outside drop below 32, then temps inside the enclosure hover around 28 degrees for many hours before the temps start dropping even more. Then the emergency heater kicks in at about 20 degrees!

I am worried about the small fan - enough said.

I just hit overload and need to crash.

Stosh

Stosh,

Hi,
We received the instruction book and a video today. .Have not had time to go thru it as yet but looking forward to.
Delivery is supposed to be around April 2'nd.

Your right, the West end of the GH will be about 18"+ above grade. The cement blocks are my idea of what will hold the earth inside the GH which is above grade. If I could come up with something lighter or simpler I would probably go that way. The cement blocks are not for carring capacity or strength at all they are there just to hold the earth back.

I hope to build a stone wall against the sides of the foundation eventually. Probably not this year as I also have to rebuild my old barn too.. I am planning on adding thick insulation boards against the foundation walls before I build the stone wall. I was also entertaining the idea of underground Insulation too but you don't feel it will do anything?
Those are my plans so-far. Your input is a God send to me and I do appreciate your time and advice, a lot!

Praying for early good weather to get outside to play with things.

Paul

I am jumping in as I am waiting on a quote from Charley's Greenhouses on the Tahoe 10x16......I am in zone 9a in Texas....she indicated that I would not need the top vents but a very powerful exhaust fan.....we always have south easterly winds even in the heat of the summer. I can't decide whether to lay a concrete slab or not. I also can't decide which direction to place it....most people down here say east to west to take advantage of the low winter sun....please add any comments for me to think about.
thanks so much....we get several close to freezing nights in January and February...so she was calculating a heater to keep the temps at 55 on the coldest nights. Does this make sense to you pros?
gail

I meant to say the name of the greenhouse is San Juan...sorry 'bout that....

This message was edited Feb 13, 2007 9:13 AM

Keywest,

I'm sorry, maybe I'm dense, but I'm not following your foundation plan at all. The way I have it pictured is the sono tubes are on the corners, the block along the sides, and the interior backfilled to bring the floor of the GH above grade. But I don't think that is right. Help!

Regarding heat, I ran some numbers. Stosh is really close. Assuming a surface area of around 500 sq ft, min temp of -10 (zone 6) and inside temp of 50, with 6mm twinwall PC, you'll need 19K BTU. That's four Walmart 1500W heaters (and, as Stosh said, for separate circuits, since each heater will draw 12.5 amps). Using a min temp of 0F (zone 7), you'll need 16250BTU to keep you at 50F. One 1500W heater will keep you at 16F, 16F above ambient.

Now Stosh is correct, it is a lot of work to install all these different circuits. However, I kind of like having multiple heaters as a backup in case of failure. In fact, I have one 24K BTU propane heater run on a microvoltage thermostat without any outside power, a second 24K BTU propane heater run off of my climate controller (dependent on outside power) and two backup 1500W electric Walmart-type heaters. If I lose power, I always have the one propane heater, and if propane runs out (it happened once) the electric heaters are there.

If you are burying lines to the GH, throw everything in that trench, even if you don't intend to hook it all up. By this I mean, put a water line, electric line of sufficient size, and why not, a telephone line as well, just in case you decide later that you want a hard-wired temp alarm.

Here is a link to a geothermal greenhouse which purports to take advantage of phase changes in heating and cooling a solar GH. This raises the complexity to a whole new level: http://www.sunnyjohn.com/indexpages/shcs.htm Stosh, I'm pretty sure there are solar panels that will drain the water when the pump is not on. This would avoid the freeze damage. I priced solar panels recently and I think a 4x10 foot panel was $600-800. There are DIY plans on the internet: http://www.bigginhill.co.uk/solar.htm

Gail, here is a GH heating calculator which may help: http://www.littlegreenhouse.com/heat-calc.shtml#area

SB, thanks very much for that link. It's very interesting to use hot air instead of hot water. That seems much less complicated than using water. The air inside the greenhouse is already heated - no use for solar panels.

Now for my mean and ugly negative side - I don't buy it. First of all, that's not a true phase change system. The only phase change they're using is one direction - moisture in the air condensing from being cooled. Where does all this moisture keep coming from? Once you squeeze it out of the air, it's gone. You can't get any more unless you put more in. Plant transpiration is one source, but in my experience, I find that if anything I have to ADD moisture to the air in the dead of winter. These last few weeks the dew point has been near 0 F. I don't have a dew point chart, but heat that air up to 80-90 degrees and you'll have something like 10% humidity like the desert. If your GH leaks at all, then fresh, cold air coming in immediately condenses any excess humidity and makes it fall to the ground where it's lost forever. And just like this "phase change" system, once the water condenses out in the tubes in the ground, it falls through the perforations and into the ground, lost forever.

Second of all, I truly don't believe there is any way to make any kind of conservation of energy work (without supplemental heat) to heat a greenhouse in our winters. The sun just isn't strong enough, isn't up long enough, and it's not clear enough. I would bet that even if it never got cloudy there just isn't enough energy in the sun to keep a GH heated to 70 degrees. For example, when it's sunny and 30 degrees outside, my greenhouse can sustain about 80-90 degrees during the mid day hours. Let's give it the benefit and say 90 which is 60 degrees above ambient. Now this only happens during the peak sun hours, so lets say that during the hours the sun is up, we'll average about 40 degrees above ambient. In the middle of winter the sun's only up about 9 hours or so. Now if you stretch out that energy over 24 hours with perfect buffering, you get about 15 degrees above ambient for the whole day. If it gets down to 0 degrees, 15 degrees isn't doing me much good, and that's assuming the sky was clear that whole day.

That being said, I'm sure that this system could save on heating costs in the spring and fall when we let precious hot air escape because it's too hot. In the summer I don't need heat at night. Either way, that is very interesting and seemingly not too expensive.

I just realized how I could beat SB's numbers from the greenhouse heat loss calculator. The north wall of the greenhouse is shared with the south wall of my house - it's home attached. That would make my numbers go quite a bit higher than SB calculated.

Also, very good recommendations on the putting in that multi purpose trench. Possibly even some kind of "data" line for use to hook up to a climate controller to monitor and/or run from the house. That sounds pretty cool.

Keywest, sorry for threadjacking, we'll get back to your GH in a minute!

Stosh, very interesting analysis in paragraph three and probably right on. That's why I said "purports."

What about going back to a simpler system which does not try to heat the entire greenhouse...your 9:44 post yesterday...

Citrus is a good example of a plant which suffers from the rapid shifts in temperature. The roots don't take up anything under about 54*F. So by 10am on a sunny winter day it might be 80*F in the GH and the leaf temperature could be higher...and the soil/root temp is still so low that the roots are non-functional...and you get winter leaf drop. If we keep the root temps higher, even if the foliar temps are low, then the plant grows better.

So what if we pump water through a solar panel from 10am to 4pm on sunny days, store it in an insulated underground tank, then at night, or starting at 12 or 2 am, we pump that water through a second loop of pipes in a raised bed or under a bench. We won't be heating the GH per se, but by warming just the roots we'll get better plant growth.

Another thing I wish I had done in my GH at the time of construction is bury a rainwater cistern under the floor. Next time...

While you are putting stuff in that trench, you should add a tube for hot water. If you are doing any seeds or propagation at all-you need warm to hot water ( I use straight hot water to mist my seeds with, and cuttings-when you use a mister head, the hot water converts to warm. Any other type of head, you have to add some cold to the hot water). When you use cold water, it lowers the soil temp and it takes about 6 hrs to get it back up to previous soil temp. I have hot water in one grhouse, and not in the other two and I kick myself everyday that I have to hook a hose up to the hot water in the one and bring it down to the other.

Hi,

Don't worry about threadjacking, it's all very interesting to me... Great ideas, A little while ago I (e-mailed), sunnyjohn about a small GH like ours ( 8x14), with the same system, underground heat exchanger w/ trunk & hoses. It sounded like something I could do & wanted his input. He wrote back & said not in my case, not enough underground piping & collection area for it to work... A larger GH yes, but not mine.
I'm very interested in geothermal, solar, & such but have not as yet found anything feasable. I'm cosidering an Evacuated H2o. system for my house thou, especially w/ the State & Federal incentives for domestic..

T will run water lines underground from my garden area, but that is not much good to us in Winter. The electric will be brought in under the whole thing before I do any construction at all. Your good advice as to size and all will not be waisted.. Charlies GH has a 240 V. Heater, 19,453 BTU @ 5700 W., looks pretty good. How about (1), 240V line for this and maybe (2), 20 amp circuts for everything else ?

I was also reading in an older thread about the use of (wet area use),ceiling fans, to help circulate warm air in winter and to act possibly as an exhaust fan in summer where I have the (2), 2x4 roof vents?? Your thoughts?

The GH site is elevated in the rear about 18" or so.... I had to do something to level the whole thing off so I have sunk (6), sono- tubes, below the frost line. That is all done, but nothing else.
These are 8" heavy cardboard tubes I filled w/ concrete and added hurricane straps to the tops of each one for anchors. This is all just to level and support the GH. A little overkill but it should stay put.

In-between each of the (6), sono-tubes I have to install (something) which will hold back the earth & stone's I use for filling up the new space. Like a big bathtub. I decided Cement Blocks would work well & not deteriorate. (8" block, 8" tube), = straight wall to insulate, I hope! I felt plywood would just rot & maybe give-way someday.?
So,.... I have to put these blocks in between each tube to create a wall which will hold every thing in. If you can please show me an easier way than all that work, I will jump at the suggestion.

Thanks a whole lot for giving me your attention. I truly do appreciate it.

Tigerlily, hot water would be good but I can't even convince my wife to let me put in a small sink. I like your idea and thanks.

Gail, why don't you call B.C. directly, 1-888-391-4433, I have had the opportunity to speak w/ the owner Henry Heinen, but usually Christene, his daughter-in-law will be happy to help you out.. Very nice people and a little less than Charlies... Nice Company.

Thanks all, Paul

Hi Paul

Ceiling fans move air vertically. It's called HAF because it moves air horizontally, mimicking wind, moving air through the foliage of the plants. My objections to ceiling fans for HAF are more theoretical than practical, and I have heard from people who say that it works fine.

Is the block mortared? On a foundation? Dry-stacked? Then the GH base will go on top of tubes and block, right?

Stressbaby,

I'm sorry....... I always seem to leave things out...

The "Sono" tubes will carry the weight. On the tubes I plan two put a double row of (4x4's) as the base plate. The GH will be fastened to the 4x4's.
The blocks will just take up space & act as a retaining wall.
I will have to mortar them together somewhat but they won't actually be weight-bearing.
Any other thought's on an easier retaing wall?

So, forget the ceiling fan, I guess?

Paul

Most ceiling fans have a switch that can either push air downward or pull up the air for winter/summer time circulation. It wouldn't hurt, I think. Tho cross wind probably is the best so the air can head outward too but I see no reason on not being able to use a ceiling fan. But just my 2 cents worth.
Carol

Paul,
Heater sounds fine. Instead of running 3 separate lines to the greenhouse I would only run one line to a sub panel inside the GH. From there you can run as many lines as you want. The line from the house to the GH would have to have 4 conductors (2 for 220, one neutral, and one ground). Yes, the neutral and ground MUST be separate lines unless you plan on installing a dedicated ground stake for the GH which I don't recommend. This main line can be protected by a 40 amp breaker at the main panel, and the main wire must be sized appropriately. Then the sub panel would have appropriate breakers for each line, 220 or 110.

About your concrete block issue - I would do one of 2 things. If the GH is to remain raised above grade, then I would probably spend the money on retaining wall block and make it look nice. If not, then I would fill the inside with dirt and not use any kind of retaining wall, just backfill a slope around the outside up to the level of the GH. Of course you'd have to tamp the dirt around where the GH will rest so it doesn't settle. You could also use stone that doesn't settle. I hope I described this OK. I'm basically saying just slope the dirt around the GH up to it and then plant grass, or whatever. Either way you do it, make sure you have the lateral insulation.

I don't have much experience with exhaust fans because I don't use them. In the summer I leave the door open along with the roof vents and the knee wall vents. This is enough to keep it reasonable in there. Here in PA we haven't hit 100 degrees in quite a few years.

Hi,

Stosh, you have given me an inspiration.
My plans were to fill in between the support tubes with cement blocks later to be hidden by a fieldstone wall.

Listening to not just myself but to your words I have been inspired to new directions.
I believe it would be easier to just insulate all around the perimiter and build my stone wall now. Instead of just window dressing I can build it to support all the dirt inside also. I'll just use a different style of stone, that's all. Great!
I think you have saved me a bunch of work.
I'm looking into this now.
Just wanted to thank you & SB & all who are giving me the benefit of their experience.

Thanks, Paul

Paul,
Glad I could help. You made me laugh out loud because the same things happens to me. I have project in my head and for some reason, the way I'm planning on doing it just doesn't seem right. After asking other people you get some really varied opinions. Usually I come up with a new plan that's completely unique, but it was inspired by somebody else's opinion. I make a lot of people angry by asking their opinion and not following it :)

SB, where did you get your name?

I built a Solar Gro (14x28) from Charley's 6 years ago. I've been absolutely delighted with the greenhouse, and even more delighted with the folks at Charley's---they're really helpful, friendly people! I put mine up on a 2 ft high cinder block foundation, because I thought the extra height would be useful (it has been!), but also because I needed a really strong foundation in case Hugo the Hurricane decides he wants a taste of Charleston again. It's a little challenging to build, but mainly because of the height you have to work at. The fit of the pieces is incredible...when I finally got to the point of installing the polycarbonate panels, there was maybe 1/16" clearance on each side, and each one fit perfectly. I cheated on the caulking, and I'd strongly advise you not to!! Fixing a leak after the thing is built is a real challenge because you can't walk on it, and the leak is always in a spot you can't reach. I went with the TwinWall poly, but if I still lived in Connecticut, I'd opt for the TripleWall. I use it as a "warm" greenhouse (min. 60 degrees) to grow tropicals over the winter, and I have to clear everything out of the greenhouse by April (gets WAY too hot). Good luck with your project---you're starting on a real adventure!

I was going to suggest what Stono did...don't fill in the GH space, just elevate the GH and take advantage of the extra space (height).

Stosh, several years ago, when researchers first began to study the effects of maternal cocaine use on neonates, they described "neonatal stress behavior." The babies were casually known as "stress babies." Well, in a really sick moment, after more than a few beers, my bandmates and I decided that we should name our band the "Stressbabies." Thereafter, I was a Stressbaby. After I was no longer a Stressbaby, I became a Tenderloin. Our singer used to say, "Please dance and get your loins tender."

Where did you get your name? Makes me think of Peter Tosh.

bettygail; Your problem won't be heating, it will be cooling. I'm in zone 8b, and I have to get everything out of the greenhouse by the middle of April, or risk cooking it. I have a 14x28 Solar Gro with 2 roof vents, 4 2'x2' side vents, and a thermostatically controlled exhaust fan (can't remember the cfm, but it's a lot). I only get 4-5 hours of direct sunlight on the greenhouse in the summer, but even with both doors open and both roof vents open all the time, the exhaust fan (set to come on @ 80 degrees F.) is always trying it's best to cool things down in there by 9 a.m. Poor exhaust fan! The temperature often reaches 100-110 degrees in there in the dead of summer. I tried to grow stuff in the GH the first two summers I had it. Everything croaked. I fear that's what you'll find. But there's a good side to it! The first couple of years I had the GH, I learned just how rapidly insects could reproduce in that warm comfy winter climate in the GH. I was going through 3 gallons of Safer Soap mix a week(no exaggeration! So I had this brain fart that said "wonder if I could cook those bugs in the summer?" So I buttoned down the greenhouse for 2 weeks at the end of July---got everything that could be heat damaged (seed, compost, rooting compound, etc) out, and locked the thing down for two weeks. Let it cook. I know it went over 128 degrees in there at some point, because that's when my Min/Max thermometer went to meet its maker. But know what? I didn't have ANY problems with severe insect infestations the following winter. Still had the unavoidable occasional mite/scale problems, but NOTHING like the monster problems I had first experienced. So there's the silver lining to the heat issue. It cooks bugs and their eggs/ larva dead. And if you spray everything completely before moving it into the GH for the winter, the minor (but inevitable) outbreaks are easily controlled. And your sun down there in texas is a lot hotter than ours in Charleston (lived in Mansfield, Tx for 8 yrs,), so don't leave your Min/Max thermometer in the GH if you choose to try "heat sterilization"...

Stono-since you have a large exhaust fan and 2 shutters(?), have you tried shutting the vents and door and just using the exhaust and shutters to pull the air through to cool it down? I have found that in my grhouses, the air moves through better without the door open. I have a 100' and 2 60' long grhouse, and it does get hot in there in April and May-and the fan runs all day, but enough to cool it down for annuals


SB-I was thinking Peter Tosh too!

Ya mon, I wish it him.
I'll try to make a long story short. In my fraternity at school they always assign "official" nicknames at the end of pledging. Sometimes the nickname is something they were already calling you, sometimes it's based on your personality or how you acted during pledging (because that's really all the brothers know about you), and sometimes it's just a mean, ugly name for "fun" kind of to screw you for the rest of your brotherhood days. Obviously everyone is a little nervous when their name is being voted on and assigned because it's permanent. When it came to my turn, they just couldn't come up with anything. Knowing I was Polish, somebody shouted out "Stosh" and they all loved it. Literally, it's the Polish equivalent of Stanley, but that's not the reason I got it (that's not my name). They told me that the name came from some old TV show that had Stosh and Stella as characters, but I never heard of it. Maybe somebody here knows what I'm talking about. Actually, the correct spelling is "Stash", but since they misspelled it, that's the way I kept it. It stuck through my whole college career and continues today. In fact it stuck so well that many people in school never even knew my real name. So in a way, my name was from a sick, intoxicated moment as well.

SB, what kind of tunes did (do) you guys do?
I realize we're way OT here and apologize.

Don't.... apologize..!!!

I find it all very interesting...to say the least...and I'm learning all the time.

Keep it up gang.....As far as Key West goes, it's more a state of Mind...........

Paul

All originals. Pop rock with a dash of country...since this is a plant forum, let's call it Nick Lowe x Graham Parker.

So Keywest, are you saying that your name is just wishful thinking? Finish your GH and you can name it Keywest North.

Yes SB,

Wishful thinking, yes - but at one time we really considered it...
Beautiful, friendly, "warm not cold", great "fishin" & water everywhere.. We do love it but here we are in "cold not warm", Mass. but this is where our family is.
Leaving everyone & everything was just too hard.

Now We are getting a Greenhouse to Capture some of that Key West sunshine & Heat... Brrr

It wasn't really Key West itself but the keys themselves.
Wicked Pissa!

Paul

I've tried everything imagineable to cool that greenhouse down, tigerlilly123, and never got more than a 5 degree variation in maximum temp. The lowest temp I got was with the front door and both roof vents closed, back door and side vents open (they open automatically when the exhaust fan comes on. Still 20-25 degrees above outside ambient in the greenhouse. I think the only answer is a cooling system like commercial greenhouses use, but I just don't have room for it.

Stono, a fellow on another forum just sent me a table: Table 18

Effect of Air Exchange Rate on Greenhouse Temperature Rise

Air Exchange / minute * - Temp. Rise Above Outside - Inside Temp. w/ outside temp 86F

2.0 - 4 - 90
1.0 - 8 - 94
0.5 - 15 - 101
0.25 - 25 - 111

* Greenhouse air volumes (length X width X height)

Example 30 ft X 100 ft X 10 ft greenhouse = 30,000 cubic feet = one volume

Source: Growers Handbook for Greenhouse Vegetable Growers, 2007 ©

The table didn't copy/paste well, but basically it shows that if you exchange the air once a minute, you will get the temp down to 8*F over outside temp, or 94*F if it is 86*F outside. Exchange the air every 30 seconds and you get the temp down to within 4*F of outside temp. Can you increase the rate of air exchange?

How big is your fan Stono?

It's dimensions are 2'x2', but I don't know the cfm. I simply doubled the Charley's recommendations, and sized accordingly. I suppose I could figure it out if I really had to, but it's so much easier to move everything out come April. I really don't need the greenhouse space in the summer months. All my tropicals seem to prefer the "outdoors" in the summer. And they CLEARLY prefer the greenhouse in the winter!

This discussion has been really helpful, as in it made me really THINK about the situation. The thermostat for my heating system is located under a bench in the center of the greenhouse. It seems to work perfectly---temp never gets below the setting (60 degrees F). The thermostat for the vent fan, however, is located just under the the fan on the sunny end of the greenhouse. I built a protective screen for this thermostat out of insulboard, so that the sunlight couldn't hit it directly, but it doesn't seem to have much effect. Today was a good example. Outside temp was 68 degrees, full sun, inside temp was 81 degrees. Side vents had opened, but exhaust fan wasn't on. Nothing else was open. Then the fan came on, and when I walked back in there, it felt cold! But the fan was still sucking colder air into the greenhouse---I suspect because its thermostat (in the sun!) was still saying "too hot", because it was in full sun. In spite of my insulboard. Think I need to mount my heat/cool thermostats in the same place...the Great Gestalt!!

I built little thermostat boxes...I don't remember where I got the idea...basically it is a wooden box, painted white, with generous holes on the bottom and on the N, W, and E sides for air circulation. One is mounted on the outside wall and the other in the central area of the GH. The controller averages the two readings. My temps have been quite even since I did made those boxes. I'll post a pic if I ever get any time...

What kind of "controller" do you have? Averaging temps from hot/cold spots around the greenhouse makes incredible intuitive sense, but I'm always leery of "controllers"... my car's already smarter than I am---I'm not sure how I'd handle my greenhouse being smarter than me...

I have a Bartlett climate controller, model GHK12x2. It has a min/max temperature record, 4 separate cooling functions, 2 heat functions, separate day/night/DIF temp settings, and a whole bunch of other functions which I don't use. It is easy to program. It uses 24VAC. Let me know if interested in details of the setup. I'm quite sure that you can handle it, Stono.

Well, that scares the bejeezes out of me! As was pointed out to me many years ago by a particularly bright young IT guy after a 2 hour session trying to update me on the "latest and greatest", he said "you know what your real problem is? You're an analog thinker in a digital world". He was right. The kid had it right! I was his "mentor', but I was NEVER going to get this stuff. Still haven't , and still don't care. It's easier just moving the contents of the greenhouse in and out twice a year. I think it's a function of age. Or the wisdom that comes with age. Or the comfort that comes with age (if it works, don't fix it!). My young friend would find this thinking abhorrent, but the truth is, we're BOTH right...