Backyard Aquaponics
A place to discuss aquaponics

I've finally started the process to get the process going to build my greenhouse.

In that today I had two IBCs delivered, and tomorrow I meet with a contractor who will help me with the foundation and everything. Since I live near the 49th parallel, having a four season greenhouse is a doozy. Therefore I'll be using all sorts of techniques I've learned here and elsewhere.

I'll have a 4'-6' deep foundation, to get below my frost line. I'll fill it with first cobbles and then pebbles. In the lower cobbles I'll embed drain tiles, and then pump the hot air from the top of the greenhouse down into the rocks in the winter, and pump the cool air from the rocks back up into the greenhouse in the summer.

The greenhouse itself will be a kit greenhouse, the harbor freight 10'x12' greenhouse. I thought about building one from scratch, but when the HFGH is enhanced, it makes a nice little setup, and it has double-wall polycarbonate. Buying that much double-poly would have cost more than the entire kit did.

I'll bury the tanks, and insulate the north wall. I'll paint everything white. I'll build a solar hot water heater. And plenty of other tricks. I'll try to remember to chronicle the process as best I can here.

This is a proof of concept (or a failure of concept, if it goes that way ). If I can run a four season greenhouse through a Minnesota winter without busting the bank, and on this small of a scale, then going larger will just get easier (heat retention wise).

So, here I go!

A few starter pics.
Bringing the greenhouse home last fall:




IBCs delivered today:



(*crosses fingers* I've had problems embedding images from Picasa before... The album is at http://picasaweb.google.com/swanberg/Greenhouse# if these choke.)

Congrats on the greenhouse. I ended up getting me one also even though I have larger aspirations of a hoop style! It really is a nice little greenhouse for the bucks! I didn't even realize it was double.
Pretty nifty how you stuffed that very heavy 10' long box in that little car!

I have the harbor freight 10x12 too. Make sure you install foam weather stripping between the glazing and the frame to help keep it air tight....and order an extra set of glazing clips!!!! the part number for the clips is somewhere in the last link.

I love my greenhouse....was thinking about getting a second one!

What zone are you in...4? I'm in 5 and it's nearly impossible to keep it warm from Dec-Feb.

Here's a few links that may be helpful.
http://www.youtube.com/watch?v=CU9x_W9X-tM
viewtopic.php?f=18&t=5098
http://web4deb.blogspot.com/
http://hfgh10x12.blogspot.com/

Web4deb, yes, I'm in zone 4. Thanks for the links.
Is your HFGH full of aquaponics? I'm wondering how much having the water in there will help with temperature regulation.

But believe me, I have a full plate of tricks to help keep it warm:
http://www.landstewardshipproject.org/p ... 081224.htm
http://www.landstewardshipproject.org/f ... waibel.htm

I've also been bookmarking articles on how to strengthen and insulate this greenhouse for a year now.

There are plants out there that don't mind a bit of cold (broccoli, cabbage, Kale and many other plants in that family seem to like cold in my experience but the cold you have there is pretty extreme) so your biggest challenge for the extreme part of winter there is gonna be keeping the water from freezing in your pipes and grow beds and getting enough light to the plants so that they can grow a little better through the short days of winter.

Good Luck with it all

D'oh! Just clicked on the youtube video... that would be a "yes."

Nice project, i enjoy seeing others doing something different.. it makes me feel a bit more normal I don`t envy you the task of shifting all that rock, the mountain of clay i excavated was tough enough. Looking forward to following your progress.

Alright, a fellow traveller. I just got my HFGH up. But I'm closer to the 40th parallel. I will watch this thread closely to rip you off, I mean steal your ideas, I mean....well, you know.

I didn`t see a mention of foundation wall insulation but i`d guess its somewhere in the plan.
If you put heat into a mass without insulating the sides, it will migrate sideways into the surrounding soil.

I thought I replied to this earlier....even uploaded a pic. Not sure where it went?

Anyway, It's going to be an uphill battle to keep your greenhouse above freezing in zone 4...but I don't think it's impossible. Mine as 1-1/2" insulation on the north wall and roof. All the glazing panels have foam weather stripping between the frame and the panel to reduce air flow. The biggest air loss was through the crappy doors which I replaced with real doors.

Last year I had a 1200 tank (heat sink) which still froze and I had to put a cattle trough heater in which kept it around 45 degrees in the tank, the air temp still would go far lower. This year I've replaced the tank with 500 gallons of water, then about 1.5 tons of stone in the GB. The thermal mass (BTU storage) is less, but I'm able to utilized the space better.

It may work to go below grade for your heat storage and extraction, but I'm fairly confident that you won't be able to pull enough heat from the ground to keep up with the heat loss of the polycarb panels - unless you install a larger geothermal system. I did the calcs last year, and a 10x12 greenhouse needs about 5000 BTU/hour to maintain a 15 degree delta from the outside temp. On a good full-sunny day, my greenhouse has no problem staying warm and having some extra heat to pump back into the thermal mass....it's the long nights and cloudy days that are going to kill you.

This winter I'm going to try the solar collectors I use for my swimming pool. The problem with them is that there is no insulation on the back side so I'll lose a lot of heat....if it's in the budget, I may try some foam insulation on the back and see if I can get some extra heat into the thermal mass. It's always an experiment.

Thanks for all of the information and links!

Here's my current compilation of links for modifying the HFGH:

Mudhouse's page.
http://hfgh10x12.blogspot.com/2007/08/t ... nk-it.html
notes on how to insulate it, and where to put weather stripping etc.

Web4Dav, of course:
http://web4deb.blogspot.com/search/label/hfgh
viewtopic.php?f=18&t=5098

Here's a good overview, but missing some pics, and some seriously lacking
grammar making it hard to understand sometimes:
http://faq.gardenweb.com/faq/lists/stru ... 05629.html

Here's a case of someone replacing the doors with a custom one:
http://forums2.gardenweb.com/forums/loa ... 15422.html
http://forums2.gardenweb.com/forums/loa ... 19956.html

Two HFGHs joined together to make a 10x24 greenhouse:
http://forums2.gardenweb.com/forums/loa ... 24451.html

Some more modifications with nice close-up pictures:
http://s47.photobucket.com/albums/f195/Gardenerwantabe/
http://s124.photobucket.com/albums/p12/ ... 12%20HFGH/

One with decent insulation on the North wall:
http://forums2.gardenweb.com/forums/loa ... 9284.html1

And heating GHs with water:
http://forums2.gardenweb.com/forums/loa ... 99.html?51

Looks like you`ve done a fair bit of research.
Regarding pumping hot air from the top of the greenhouse down into the rocks in the winter, and cool air from the rocks back up into the greenhouse in the summer.
The mass won`t retain heat or cooth over an extended period of time unless its really huge and seriously well insulated.
In summer, a few hot days will reduce the capacity of the mass to provide any cooling power. As autumn arrives, the night temps drop causing higher losses from the mass and reducing the reserves well before winter sets in.

Greetings from Wisconsin.

I have similar goals in mind, and will be eager to hear how your year round setup works out.

Unfortunately, Hex is correct. The size of the HFGH is not large enough to collect enough heat during the day in the winter to heat enough thermal mass to act as a reserve for heating at night - especially in zone 4. 6+ I bet it would work. You're probably going to need some type of "outside" heating source: Solar panels, propane heater, geothermal heat pump, etc.

If you figure out some magic way to do it, let me know!!! I'll do it in mine!

this all seems pretty cool if it works out that you can stop your water from freezing and find some fish that will survie the winter then your in business

i like your ideas and would like to see if it all works out
if i does then it would be possible for me to keep something like Barramundi or jade perch over winter

hope to see a few more pictures soon