Underground cave

[Cheese Head]

Great thread, links and picture, really puts it in context!

[Tropit]

That's a big cave.  I've heard of burying a modified shipping container to use for a wine cellar.  You're looks even bigger...I'm jealous.

[coffee joe]

Actually, once done, this will be about the size of a shipping container 13' X 24' , we need space around to work. There will be 5' of soil above the top of the roof. After it is all done, we backfill.

[Tropit]

Well...it looks great so far.  What will the front look like?

[coffee joe]

While I'm still designing how this will look in the end, I know I need to fill the front with a wall to hold all that earth. Our traditional "building blocks" are hand hewn granite blocks from our quarry. The entire cave will be made out of these. The photo below is an idea of what the finish will be inside and out.

[linuxboy]

Wow, amazing. Are you keeping a natural dirt floor and/or whitewashing the walls like the Europeans do it?

[coffee joe]

I will be using polished concrete for the floor, we do have health inspectors here too! As to whitewash, I am hoping not to need this but lime is easy enough and a probable requirement. At least Lime won't give me weird odors to deal with.
As to the health inspector, he is watching us go through the design and construction, not quite at ease with the whole idea, but is going to let us continue with the understanding that our product will be thoroughly tested.  The porosity of the granite bothers him to no end. It is just that porosity that will be our primary humidity control, so I hope he doesn't make me tile my nice walls.

[coffee joe]

While it may seem like I know what I'm doing, I am doing this project based on having been to a few natural caves in Europe and reading allot. I was pleased to be shown the Estrella cave in Washington as well. Construction and Cows I understand!
I know there are pitfalls in doing this type of cave, and would appreciate any on this forum with experience helping out.             
                                                 Françoi?

Air flow I have a max of 17 X cave volume per day, more than I should need and controllable for less.

All air, besides when I open the door, will enter through a heat exchange made of 6"PVC pipe wrapped around and under the building, air coming in will be filtered and ground temp.

Temp control I am planning on a 24,000 BTU Split A/C with a coolbot. Our deep ground temp is about 62º-65º year round. So I'll be using a 2" foam insulation on sides and roof to help keep to 53º - 55ºF  airconditioners don't control that low, at least not here.

Ground level air flush for NH4 will be manual with a computer type fan on a timer.
Hot air flush at the roof line will be convection and fan over ride if needed.
Humidity and temp will be monitored by an Oregon Scientific unit that I hope to make adaptable to an automatic water mist/spray against the stone walls. 

Entry will be sterile conditions with footwear change, hair bonnets, hand sink, double doors with the interior door being sliding glass thermal pane. Cheese Entry/Exit will be through a small opening away from main door so I don't need to open the big door. These items are the health inspector talking.

What am I missing?

[FRANCOIS]

I have consulted on a number of caves, for both farmstead and larger commercial production.  Where do I begin?

Air flow should ideallly be based on air speed (emulating a natural cave), as a minimum you want 5 changes per hour.  You have it right that you should be exhausting from the floor and dumping fresh air in from the top (hopefully on opposite sides of the room). 

I personally wouldn't use a residential air conditioneer as they aren't built for high humidity, mold spores and ammonia, not to mention the fact that you will have to hot rod it to get temp control.  You'll be amazed at how abused the equipment will get in a cave environment.

The big question everyone always has is fresh air.  While I orignally developed the ground sink intake concept and calculations that everyone seems to be using, everyone seems to forget two important points:
1.  I intended it to be used in a cave with no electricity, a solar chimney was the exhaust and the intake had to be totally passive in cooling.
2.  It is inherently uncontrollable.  I knew this designing it and it is calculated for worst case conditions. 

If I had a choice and electricity on the site I would use a proper ERV and be done with it.

Your last question around humidity control.  I had the best luck with a digital Honeywell unit onnected to a well water line (and booster pump relay) that fed agriculture misting lines.  Be sure you use a fan lockout otherwise when your cooling fan comes on it will trigger low humidity and your mister then comes on....the result is wet mist being blown around the cave and condensing on your wheels, not pretty.

Any more questions, just ask.

[coffee joe]

Been a while but we finally got the foundations in and starting on the walls. Everything pictured is still below the floor line.

[coffee joe]

Another month gone by and we finally have the inner walls up, the thermal floor made of Autoclave Cellular Concrete blocks is done as well. Next step, concrete the floor, install air flow pipes, insulation in the walls and backfill. The barrel ceiling will be the last step, with luck, a month from now.

I've never used the ACC blocks before but what a great product. For walls, or under floors an easy to use product that gives great thermal protection anywhere drywall can't be used.

[DeejayDebi]

It's really starting to come together - go get em Joe!

[coffee joe]

A couple months later, and we are ready to pour the roof of our cave. If all goes according to plan, Mid January we can start aging CHEESE! Certification will, hopefully, be done by then as well.

[tnsven]

This is INCREDIBLE! Where are you located again, Joe?

And where is that high up picture taken from?

Kristin

[coffee joe]

Kristin,

We are in Minas Gerais, Brazil. The first pic is from the hillside across from the cave.