I would LOVE some advice/help I am building a underground tire walled greenhouse

So far I am 3 foot in the ground with tire walls about 70% done at 5 foot high. The greenhouse will be 80 ' x 40' outside the tires and roughly 74' x 37' inside.
Im looking for any advice on construction of the top.

Should I use hoops, wood frame, stright wall? Ive thought about pvc hoops. I have a lot to concider I know.

also what covering I have read many of the topics on this some prefer double layer of plastic some polycarbinate some solexx

Ill have more detales latter and some pics

thanks Jared

Jared; I've had sollex on our greenhouse for 4 years now and we love it ! Spendy to buy, but the rolls sold by the linear foot came with free shipping (at that time) nice even opaque lighting, no air gaps at walls or peak, an R value ! Sheds snow , 10 year warranty on uv . No air pump ,no replacing plastic every three years, I would not have anything else!

I have been trying to put some pics up. I just figured it out.

Substantial greenhouse you've got going, looks great! What do you plan on growing with it?

Do you need to worry about snow load? Major wind?

I used the cheap-ish corrugated plastic roofing sheets on the tiny little 8x12 I built on my parents land. I intend to use something fancier like Solexx when I eventually build one for my own long-term use.

I've seen quite a few hoop and poly greenhouses turn into tattered messes from lack of plastic replacement, and I don't like the waste of the more frequent plastic replacement. It would likely be the cheapest/fastest way to get going, though.

My goal is to grow enough food for greens and fruits for the family. I want to grow year round. I have considered many options for keeping it warm in the winter. Such as heat sinks, geo thermal, rocket stove, or a combo of any of those.

Any Ideas in that regard (to heating)

I'm in NV it is down to the teens sometimes in the winter ive even seen it below 0 a few times for like two weeks

Snow not too big of a deal but we do get some maybe a few inches here and there sometime 12 inches would be a bad storm. Most of the time it melts off within 24-48 hours or sooner.

Man. I can't imagine how achy your back must be packing all of those. Kudos to you!

We're talking 0 degrees F, right?

How are you fixed for fuel? I just learned that Nevada is the driest state, so I don't imagine you'll be growing a lot of firewood? Any important fuel resources available that might influence your choice here?

I haven't any experience with trying to grow year-round, as there is simply not enough sun for much anything to work without additional lighting up here it isn't something I've tried yet.

That said, I would definitely suggest a combination system, because redundancy is good. I like redundancy. Redundancy is good.

Rocket stove as backup or emergency boost for extra cold days seems like a good option.

For the primary heat, I would distinguish between heat storage (heatsinks, extra thermal mass like barrels of water, cob benches, tires full of dirt...) and heating(rocket mass heater, woodstove, electric, oil furnace, geothermal despite the fact that it seems a lot like a heatsink).

Is it possible to get by 99.5% of the time with heatsinks and plenty of thermal mass, in a dug-in greenhouse like yours? In your climate, I really don't know. Obviously much will depend on your choice of coverings. If it is possible, that would certainly seem optimal.

Even if it is not possible, you would still be seeing benefits from the passive systems, and would have your backup heat source to fall back on. If you find you must light that RMH more often than you would like, you could then move on to a geothermal installation for primary heat.


On a bit of a tangent, aquaculture/aquaponics of a warm climate species like tilapia would dovetail really nicely with a big greenhouse needing heat; the water would be additional thermal mass, and the fish waste a valuable nutrient source for the plants. You'll have the space! Is this on your wishlist?

We're talking 0 degrees F, right? Yes F.

Not great for fuel I have 2 1/2 achers of land When I bought it There was only weeds no trees no knowthing. that was about 5 years ago. now we have 19 fruit and nut trees and around 12-15 cottonwoods
Hopefully I can have some fuel latter but it wont be much.

I am all for Redundancy it would be great if I could get 2 or more things in place. Rocket mass heater for sure heat sink yes! not sure about the geo thermal though It is expecive and alot more work to install.

I like your idea for a aquaponics as additional heat sink and would love all the benifits from it as you metioned (and the fish waste a valuable nutrient source for the plants. You'll have the space! Is this on your wishlist?) yes it is

It is all about time and money! lol we will see . Thnks for the help

Are there other trees which will survive in your biome which can be coppiced or pollarded? I'd think those would be very valuable techniques in this situation, keeping the precious deep roots of the mature tree while still harvesting fuel. Looks like cottonwood does coppice well, so that's great!

Fuel shortage definitely confirms that a combustion device would be better as a secondary heat source...

If heatsinks/thermal mass are not sufficient for primary heat source, the only other non-combustion options I can think of are:
-geothermal, already mentioned, expensive
-Solar, either direct via vacuum panels, or photovoltaic as per: https://permies.com/t/45425/passive-solar/Passive-house-PV-electricity-heating#364288 (still expensive though)
-heat-pump, not sure if this is even possible at such low temps, doubt it

One nice part of radiant heating from solar of either sort is it would allow you to heat a mass... and then put plants on it. Bottom heat for propagation, built right in!

Don't forget about summer cooling; I expect you're planning for shade cloth and hopefully earthtubes for cool air input?

Insolation(hours of sun per day) in Nevada is really high in winter.... http://www.bigfrogmountain.com/SunHoursPerDay.html

Your winter low is as high as the yearly average up here! Definitely a point in favor of solar, and will certainly be a big help to your heatsinks and any passive collection systems... Promising!

Thanks Dillon for all the info It give me some ideas when I get the time I will research some more. I am still learning about some of the things you mentioned.

Like coppiced or pollarded