Underground Pods

[Dynamis]

One of my projects this year is to build an underground storage pod. I am looking to build it in the 16'x16' range with an 8' ceiling. There are several companies that make pods that you can place underground but what are your thoughts on building one from a treated wooden frame with a cinder block outer shell and plywood interior liner? Would the wood need to dry out for a period of time before it would be safe enough to be confining within it short term?

My plans are to use it primarily for food, water, few guns, ammo and low temp storage as well as a residence from any catastrophic event such as tornado, severe weather, radioactive fallout, etc should we need to live underground for up to 2 weeks(ish).

Also, what are your thoughts on adequate ventilation?

Please chime in.

 

[klarktx]

I would certainly install a vapor barrier between cinder block and wood. 4 mil+ would be preferred. Also consider a small simple humidifier installed.

How far below are you thinking? ceiling to ground level?

 

[Dynamis]

How far below are you thinking? ceiling to ground level?

Probably 12" or so.

 

[klarktx]

For ventilation, I would think a small (1000 cfm) air scrubber with HEPA filter chamber would suffice for approx 3 air changes per hour. Port or draft through hard pipe into a plenum to unit in basement. I could help you select and get a great price on one of these units.

 

[Dynamis]

I would certainly install a vapor barrier between cinder block and wood. 4 mil+ would be preferred.

My initial thoughts are to roll on a tar based waterproof coating, but then again I am not looking to asphyxiate myself or my family should we need to get in it.

 

[Dynamis]

For ventilation, I would think a small (1000 cfm) air scrubber with HEPA filter chamber would suffice for approx 3 air changes per hour. Port or draft through hard pipe into a plenum to unit in basement. I could help you select and get a great price on one of these units.

I have (3) Austinair Healthmate HEPA floor units that move 250SQFT per minute, but unfortunately I don't have a basement. I would be putting it right between my house and workshop.

 

[klarktx]

I said basement on accident. Meant pod/ shelter.

I am thinking your units would do nothing to bring in outside air. If this is intended to shelter from nuclear/ biological, etc....then thats not a factor....but you can filter air with simple HEPA or we use charcoal filters at times for stronger purification. You would need one way input air flow to and exit exhaust to create negative air pressure to insure air quality inside.

I perform mold jobs in commercial properties in somewhat the same way

 

[klarktx]

My initial thoughts are to roll on a tar based waterproof coating, but then again I am not looking to asphyxiate myself or my family should we need to get in it.

This would help with waterproofing and rot prevention or inhibitor. But you would possibly develop a mold issue from internal condensation without this proper ventilation.

I will think more about it

 

[ATLEMT]

I think it's a great idea, I'd be hesitant to use too much wood underground. Have you thought about how you plan to enter the space from the outside as well as any reinforcement in the center to support the weight of the ground above it. I'm no expert but those are justtwo things that popped in my head

 

[drtybykr]

Put the tar on the outside of the block wall, something like karnak, then cover with black 6 mil plastic plastic. lay a french drain around it.