A root cellar between large boulders?

The typical construction for a root cellar is out of my budget, we don't have a basement or extra room in our very small house for a cool cupboard, but I want something bigger than a freezer in the ground. I have this idea that I may be able to make a root cellar between two large boulders on the back of my property by building a roof and door between them. There is a mound of soil between the rocks towards the back that could be removed to make more room. The photos and snow don't show that the boulders wrap around the back so that the "alley" between is sheltered on 3 sides. Would such a thing work?

I think it could work very well.  I would think you will need to insulate the roof and door heavily, but I think it's a great idea.

Looks like a great starting point to me. How high will your storage space be? Is there pretty convenient access from your house? How far apart are the walls? I look forward to following your progress on Permies.

Steve Mendez wrote:Looks like a great starting point to me. How high will your storage space be? Is there pretty convenient access from your house? How far apart are the walls? I look forward to following your progress on Permies.

The first photo was taken from the back step... it’s very close to the house, not inconvenient at all. The taller rock is ten feet tall and the smaller one is seven feet. The roof would be sloped. The walls are about 5 feet apart.

I would love to have that on my property.  I'm fascinated by huge rocks.  I think it will be awesome.  It could double as a fantastic storm shelter.  Please post pictures when you are done if you decide to proceed.

The size certainly has potential to be useful despite the extra material you'll have to add. I was looking at something similar on my property, but decided it was just too far from the house. Having rodent-proof cool storage for fall veggies/fruit is really worthwhile as once it's built it will need little extra effort/energy to keep food longer.

Jay Angler wrote:The size certainly has potential to be useful despite the extra material you'll have to add. I was looking at something similar on my property, but decided it was just too far from the house. Having rodent-proof cool storage for fall veggies/fruit is really worthwhile as once it's built it will need little extra effort/energy to keep food longer.

How would you go about rodent proofing the dirt floor? Pour concrete? Forgive me, my building knowledge is next to none and I have much to learn.

What a neat opportunity!

Rodent proofing could be done with brick or concrete pavers as a floor, the joints between would make it semi-permeable for moisture to enter or escape/drain away. (where concrete would not).

More important would be sealing the boulders at the back, and having a tight door at the front. Sealing that front wall to the boulders, and having a solid foundation for it to sit on might be the easier part. Sealing up the fissures in the rocks at the rear will take some doing, If it were me, I'd excavate well below the intended floor level and seal up any fissures, before setting the floor.

Depending on your climate, you may not have a rodent problem. If it were me, and I did have that issue, I would make rodent proof containers rather than trying to rodent proof the whole structure.  Boxes made of a simple wooden frame and hardware cloth with 1/8" or 1/4" square mesh will keep the rodents out.  It would be harder to rodent proof a structure I think.  Mice seem to be able to get through spaces I would never believe if I hadn't seen it.

I agree with Trace.  Rodent proofing the bins would likely be easier.

That will be a nifty root cellar.  Maybe attempt a round door and it would look like a hobbit house.  Or maybe dwarf house...

I'd think the rocks would moderate the temperatures well.  I'm not sure how quickly it would come down to storage temperature and if it would go below freezing.  It's probably hard to predict.  Allowing ventilation in the mid fall to help it cool down on cold nights may be helpful.  Having an insulated roof and front may also be well worth it.  You might accidentally have a freezer in the middle of winter depending on your location.