Just built myself a Harbor Freight 6x8 greenhouse. Not the best option, but I did beef it up good. My question is in regards to the flooring. I know the earth gives off some heat, so I’m wondering what would be the best option for containing as much heat as possible.
I’ve read that pea gravel and concrete hold heat well, but is just the plain ole dirt better for that?
Nice assembly! The issue during colder months is ground water that either flows or settles under the greenhouse. I would recommend a platform containing at least R-23 insulation.
Richard,
So you’re saying it’s better to contain the heat produced from the sun rather than use the heat from the ground?
During the colder months, soil moisture under your greenhouse will be in the 35F to 45F range. Without insulation it will act as a heat sink – removing heat from your enclosure.
Now it is true the the earth has embedded heat, but to harness it you will have to remove surface interference. To do so is quite an engineering project.
You should watch some youtube videos on “climate battery”. That involves excavating the ground but one advantage is takes up no space in your greenhouse. Otherwise you have to build thermal mass in the greenhouse and this takes up space (rock/concrete wall, black water barrels, etc). You should always insulate the north wall because you don’t get sun from it but lose much heat.
Neither does putting an insulated platform under your greenhouse and it is far more effective.
plain wood? or is there something better you would recommend?
nice greenhouse!! how tall is it to the peak?
It’s just over 7 feet at the peak.
what do you plan on using it for? veggies? or something more intense?
No.
In the winter months I store my dormant subtropical trees in there. Not sure what I can do with it in the summer yet.
Richard. I was thinking cardboard on the bottom level. Then the R-23 insulation then pea gravel on top. I just want to make sure the pea gravel is ok unless you have a better option.
Will drainage be an issue?
In early march the odd year my greenhouse floods a bit. The worst I ever saw was 3 inches in some places. That’s with a dirt floor, you can imagine the mess. I ended up putting tarps down once it dried up
I would just use a weed barrier and some wood chips.
Unless you heat it, then it might not be enough to protect your tropicals.
The temperature will be dipping way below zero inside this structure.
You don’t want the insulation to get wet.
True.
Ross: how long did it take you to put together that greenhouse? I got the same greenhouse as a birthday present from my husband, he hasn’t put it together yet. Still in a box somewhere. Just wondering how much of a project it is.
Took my Father and I 3 days to build the foundation, greenhouse & to reinforce it.
Another 2 days insulating it, and another day getting electric out to the greenhouse for a heating system.
Oh wow! That’s a project alright !