A Community and Forum For Aquaponic Gardeners

Insulating material for greenhouse construction

Over the winter I purchased a used steel framed greenhouse. It is 45' x 15' with 8' side walls and a peak height of 17'. I am planning on constructing the greenhouse this spring. It will be south facing and have a concrete foundation. I am trying to decide what material to use on the sidewalls and the roof. I want it to be well insulated because winter temepratures are routinely around 20F with lows around 0F. IT also has to be well ventilated for summer temperatures reaching 90-100F. I am considering using polycarbonate panels for the south facing wall and the roof to let the light and heat in. I was thinking of using a better insulated material for the north east and west walls. Does anyone with construction experience have any suggestions on what kind of insulated material to use. I have not purchased any of the building material yet (other than the frame) so I am open to any suggestions. I would like to keep the costs down but I am more concerned using the best materials to regulate the temps easier and limit my heating bills.

FYI the concrete foundation has not been built yet either so if anyone has any suggestions about insulating a concrete foundation I would appreciate the info.

0 members like this

Replies to This Discussion

Permalink Reply by Jim Fisk on April 3, 2013 at 2:32pm

An old belt driven hot air sg cage blower handles heat far better than the newer "in the fan" type motor in my experience using them for whole house attic fans (from the dump of course).

Vlad, here is a pic of my blower damper. Easier to adjust than duct tape

Amazing how small I set it to get a full blaze, fan on. Then when the stat is satisfied it idles way down. (the fire that is)

Permalink Reply by Jon Nose on April 3, 2013 at 2:40pm

Tried the inline duct booster type fan but it kept over heating and shutting down so I went for a bigger squirrel cage type fan from my local Hydroponic shop and it chugged along with out a problem.

Rocket stove is constructed with fire bricks but used 8 inch round steel pipe (1/4 inch thick) for vertical combustion tube. and my in ground pipes are all 8 inch as well. burn chamber etc was kept at 7 inches.

pics here http://community.theaquaponicsource.com/photo/albums/rocket-stove

Permalink Reply by Vlad Jovanovic on April 3, 2013 at 3:04pm

Hehe...cool Jim. I'm betting that's (at least) a mid pressure rated blower (unlike the low pressure blowers SJ was using). I think SJ has to use relatively small blowers since 'the trick' is to move a large volume but at a slow speed...since contact time is paramount...at any rate, appearently, in their application, the problem ceased when they switched to the in-line type.

Awesome pics Jon (I dig the 'Lady of the Exhaust:) ...So how cold does it get in Duncan?

Permalink Reply by Jon Nose on April 3, 2013 at 3:39pm

Yeah the lady is still waiting to be transformed into a Mermaid ...

The water temp this winter did not go below 40f went as low as 32f previous year but did not have the sump tank up and running then. If there are clear nights during the winter will freeze .. the lowest I can remember is -5 c . but this winter think it was about 80 percent over cast .. snowed once or twice but usually gone in a few days. I reside more on the southern part of the island .. sort of the Hawaii of Canada.

Permalink Reply by Vlad Jovanovic on April 3, 2013 at 4:06pm

Well, she looks good anyhow...(Could maybe use a bit more thermal mammar...er...mass :)

Wow, that's not too bad at all. It got down to -28C here last year.

Were you maybe rig up a little water heater atop the RMH?

Permalink Reply by Jim Fisk on April 3, 2013 at 4:23pm

I love the way your build brought out the sculptor in you. Too bad you couldn't feed long 4x4s in real slow

All that thing needs is an auto feeder. Great project.

Permalink Reply by Jon Nose on April 4, 2013 at 8:42am

Was thinking of trimming the mass so that the thermal mammar was a little more pronounced :)

-28 ouch

Been playing with the idea regarding the water but no clear vision on it yet. Also have a seasonal creek where i am toying with the idea of running a small generator .. enough to run some lights etc for winter operations.

Vlad Jovanovic said:

Well, she looks good anyhow...(Could maybe use a bit more thermal mammar...er...mass

Wow, that's not too bad at all. It got down to -28C here last year.

Were you maybe rig up a little water heater atop the RMH?

Permalink Reply by Jon Nose on April 4, 2013 at 8:49am

Yeah... Michel Angelo eat your heart out ... will post a pic when finished..

about the longest I have been able to run is about a foot. Been thinking about contacting the crews that do the hwy and power line tree trimmings as they put all that stuff through a grinder ?

Jim Fisk said:

I love the way your build brought out the sculptor in you. Too bad you couldn't feed long 4x4s in real slow

All that thing needs is an auto feeder. Great project.

Permalink Reply by Paul Phillip Meyer on December 16, 2013 at 4:18am

Hey Cliff. So what did you decide to do for insulating your greenhouse? I'm seeking to rent one but it is already built with just one layer of poly on it. I'm considering air blowers and just doing a second layer with some type of heat source inside. However, I plan on building my own (much smaller on some off-grid land so let me know what you finally did)

Permalink Reply by Cliff Dillon on December 16, 2013 at 9:46am

Paul, I ran into some financial issues so I got a late start on the construction project and I did not finish it before winter set in here. Since my last post, I did excavate the site and pour the concrete. The concrete was poured 10" thick with an additional 4" of R10 insulated panels and is 42" deep (below frost line) and 10" above ground. The frame has been built but none of the walls have been constructed. I am hoping to finish it next spring now. As of this post, I am planning on using 10mm polycarbonate panels for the entire greenhouse. However, if someone has a better idea for the side walls I am open to suggestions. I have attached a picture of what I have done so far. If you look closely at the photo you will notice one span is missing in the photo. That span has been completed too but the photo was taking before it was finished.

I am also planning to put gutters on the North side of the structure and building a large gravity fed water catchmen and drip irrigation system. The drip system will feed into the greenhouse and also feed into the garden located north of the greenhouse.

Permalink Reply by Linda Logan on December 16, 2013 at 10:42am

There is a material called Fclear (or something close to that) that a man named Jason Garvey can get. It comes from Germany and has 100 year life and better than glass for light transmission. It can come double walled for insulation. You've done such an awesome job in the foundation you might want to go the length to do this. Check him out, I'm sure he has a profile on this site.

Permalink Reply by Cliff Dillon on December 16, 2013 at 10:51am

ok Thanks. I will. As anxious as I am to get this project finished, I want to do this right even if it means waiting a little longer to pay for a better quality material. At least initially, I will not have supplemental heat for the greenhouse and am hoping if it is built well, I can heat it with just hot compost and maybe a subterranean system of some sort. I would like to keep the temps above freezing year round. I don't need to have temps in the 70's or 80's but if I can keep it above freezing I can use it to keep cold weather crops and maybe even winter over some warm weather potted trees.