Underground building

[Dies Irae]

Hi,

Question to any miner,digger or dwarf around.

I managed to make a small storage underground. Nothing too deep or fancy, just a hidden ladder and small space to hide most precious supplies.

Now i need to make it larger,more secure and expand it.possibly make more rooms and go deeper.

That brings up my questions.... i dont have any skill with building underground. How big can the room before there will be a danger of collapse? Is there a depht that is safer to build that others? There is a small building above it already and my ladder is hidden in its basement.... will it help to use concrete (possibly hardened with rebars) and make rooms with it or it wont matter because of the weight of the ground above it?

Got tons of questions ( some are basic,some are hard to answer and some are just efin stupid )

Any tips and info is apreciated.

 

[Proud Prepper]

Wood works well and is not costly and easy to come by. A 6x6 beam and posts is recommended. Use 2x8 for the bottom as a mud SiL .

 

[Brent S]

Wood is quicker and cheaper but dosent last as long. Concrete reinforced in steel is much stronger and safer. Look up my old thread about building my root cellar/storm shelter. It was fairly simple construction and will still be there in 100 years. Moisture is a major consideration in any build underground, so thought needs to be given to airflow and circulation. No matter what you build keep safety in mind while doing it. Suffocating in the dirt from a side wall collapsing or cave in sounds like a bad way to go.

 

[Proud Prepper]

Wood will likely last longer than he will.

 

[Maverick]

Cement will probably be cheaper but if you're stuck with wood, Use western red cedar or redwood or cypress for exterior interior walls with the interior lined in ceder, as far as collapse it depends on the soil and moister content as Brent eluded to above. Digging underground will require beams with them cleated at the top, beams spaced 6~8 feet apart, similar to the technique of late 19th century early 20th century mining caves.

 

[Brent S]

Wood will likely last longer than he will.

Yeah, at my age now long term planning dosent need to be as long as it used to!

 

[Dies Irae]

Taking notes .

Thank you Brent to pointing me to your older thread. That will help a lot.

Found a guy nearby that is offering these for free.

Hes got 7 of those ... remains from a finished building. So a free upgrade for me.

Hoping to make a small shelter where my family could hide for few days if neccesary. Thats why i thought about concrete at least for a small room.