Concrete – 1960s bomb shelter a safe place to wait out a tornado

concretesafety

I have a 1960s 10x12x8 ft concrete room. It was built under our concrete kitchen floor which is at ground level in 1963. The concrete is 12" thick, except for the ceiling which would be about 24" thick. I do not know if it is rebar reinforced. It has a 36 inch doorway opening in the basement and is otherwise 100% concrete. The doorway just has a simple hollow core door.

This was built in the 1960s when everyone was afraid of nukes. In recent years however we've received a lot of local tornadoes that touch down within miles of me. Last night we had one right on top of us (took out a few houses near us) and we all used this as a shelter. Is this a decent shelter or not? What should be done to it in order to make it a safe shelter? Assuming it should have some sort of shelter grade door instead of the interior hollow-core it has now? There is no venting in there either. It appears to be the start of a bomb shelter that was never finished.

Best Answer

I agree with @paul: the room should be adequate for protection from a tornado.

However, a bomb shelter was/is designed with different assumptions than what one would design a storm cellar for, primarily that once the bomb shelter is occupied, that there would be no hurry in opening the door for quite awhile. Also that there is little need for outside communication since it is generally assumed that the phone company is gone and probably all radio stations.

A hollow core door is something of a concern due to over-pressurization and under-pressurization between the room and the kitchen during a storm could (and probably will) bust up the door and turn it into nasty projectiles. A nice heavy solid core door is much more likely to perform satisfactorily. It is possibly better to have no door than a hollow core.

Items to consider adding:

  • A cell phone repeater located just outside the shelter should easily be able to receive cell phones from inside where the 12–24 inches of concrete might make cell phones otherwise useless.
  • A pry bar, handsaw (for cutting lumber), hacksaw (for cutting rebar), and sledgehammer would be good insurance inside to be sure you can get out when it is time.
  • Several battery powered lights
  • Plenty of water and food
  • A porta-toilet
  • First aid kit
  • You are carrying your cell phone into the shelter with you, right?

In all likelihood, you would be in the shelter for only a few minutes less than once a year. But having the supplies to be comfortable for several days is great insurance even for non-tornado events when you wouldn't even use the shelter.