We added GPS coordinates to ours in Warr Acres just in case. Things probably won't look the same afterwards.
An engineering curiosity, but does anyone know how those steel above ground shelters are attached to the floor?
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Bolted...with high-strength bolts. Mine uses eighteen 1/2" bolts that are about 4" into the concrete.
ETA: I should mention ours was installed on existing concrete. When they're installed with a new slab of concrete they usually will have a different type of anchor that's placed into reinforced concrete.
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My inlaws had one installed. They were attached by anchors that went into 3 or 4’ holes & were filled with concrete.
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www.fema.gov/sites/default/files/documents/fema_safe-room-foundation-anchoring_fact-sheet_10052021.pdf
There are videos all over YT showing various testing regimens...from firing 2x4 boards at high speed (for penetration testing) to driving cars into them, to dropping cars on top of them, to shooting them (though I think that's more for fun than anything else).
There are videos all over YT showing various testing regimens...from firing 2x4 boards at high speed (for penetration testing) to driving cars into them, to dropping cars on top of them, to shooting them (though I think that's more for fun than anything else).
I think I'd rather have something through the slab and into the ground, but I'm sure the math behind 18 bolts works too.
Visions of the 99 path will probably always make me go underground though, lol.
As others have said, they're bolted down.
BUT..... The next question is how are the bolts FASTENED to the floor, that's where it gets trickier.
Most above ground garage shelters are 'bolted' to the floor using epoxy resin glue to attach the bolt to the concrete. It's easy for the contractor and lasts a good time.
Until they don't - read page 3.
https://www.okshooters.com/threads/...d-storm-shelter-recommendations.241458/page-3
Epoxy glued bolts and expanding wedge (Red Head) bolts can come loose - without visible evidence. (Due to thermal expansion cycles, it can loose it's bite)
I prefer the 'Power Fastener Wedge bolts'.
Positive interference engagement (threads).
You must use the proper size drill bit, and there is 'edge margin' requirements. Other then that it'll never fail.
Same consider goes for gun safes.
I've learned over a lifetime to never rely on 'never' as being forever. Lot of people burned over things that should 'never' have occurred.
Seriously, that's your contribution?
"Never say never"?
Ok, I concede - everything can fail, even the recommended 'power wedge bolts'. But the professional safe movers are what strongly recommended them. The rest of the info is still valid.
...Or were you agreeing with me regarding the epoxy bolts/expanding wedge bolts?
Your response could go either way....
We have the in-ground garage type, saved my life once.
I appreciated I could watch the news and gradually get the cat and 2 dogs down there as the storm came closer, then I got in and closed the door.
Would have been a giant PITA getting the animals in an outdoor shelter in the rain, hail, and wind. Even more so if it had been after dark.
I appreciated I could watch the news and gradually get the cat and 2 dogs down there as the storm came closer, then I got in and closed the door.
Would have been a giant PITA getting the animals in an outdoor shelter in the rain, hail, and wind. Even more so if it had been after dark.
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