In my basement I am wanting to put a storm shelter. It is a 4″ concrete slab, and under that is plastic underlayment and about 4 to 6″ of stone. The ground underneath is pretty much solid sandstone. I was wondering if I could put a concrete block wall on top of the slab, if I would need to drill holes and drive in rebar, or if I would need to cut the concrete, dig out and pour other footers? The edges of the slab rest on about 3 to 4″ of the footer. I am only wanting a 7′ wall with a metal or concrete roof on it. Any help would be appreciated. I have not seen any evidence of settling problems in the basement.
Discussion Forum
Discussion Forum
Up Next
Video Shorts
Featured Story
![](https://images.finehomebuilding.com/app/uploads/2024/05/23122928/01232448-bracing-for-storm-thumb-16x9.jpg)
Insurance industry research shows that stout roofs, strong windows, and metal connectors can help protect houses from high wind, hail, and hurricanes.
Featured Video
How to Install Exterior Window TrimHighlights
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Replies
I'm assuming a tornado shelter? A 4" Slab is just not enough to anchor anything substantial to. I would cut the slab and pour a footing (depending on the size of your shelter a thickened pad for the shelter might be the easiest way). I would build the walls like a concrete retaining wall. Also I would pour concrete instead of block. The block needs to be grouted anyway, so just build forms and pour concrete. I started construction building forms so I am likely biased in that regard. Good luck.
In general I agree with Greg, but given what your trying to accomplish, talk to a structural engineer. If I was sitting in the shelter, I would want to know I did everything I could to protect my loved ones sitting next to me, while the world is trying to destroy me.