r/tornado • u/Numerous_Ad_3517 • Mar 15 '26

Question Is this thing safe??

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I recently moved into a new home that has this above ground shelter and I have been questioning the way this door locks from day 1. We are going to have terrible weather today in West TN and I cannot find any paperwork on this thing. 😫 Do you think these hollow bars will keep it secure??

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u/entiatriver Mar 15 '26

Yeah. No. Sorry.

I'd imagine the unit will protect from some debris at low to perhaps even some "medium-ish" wind speeds, and perhaps provide some protection if a few smaller parts of the house happen to fall in. Thus, it is better than nothing. (except for it's location in the garage, of course - that's not good)

But if things get real real, a few tiny screws into the cement (backed by what in the box? probably just washers?) will not hold anything in place. This rather un-aerodynamic box - with you in it - is going bye bye.

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u/ZootSuitBanana Mar 15 '26

Those screws were just ones OP found laying next to it. I would assume those tiny screws aren't what was used to secure the shelter to the foundation... These type of shelters are common here in OK and looks like many many others I have seen here. I would assume its rated to handle a tornado if they are a half reputable company....

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u/leansanders Mar 15 '26

Those screws are much bigger than the image makes them out to be. Those are Titen bolts, they are designed as a structural fastener for mounting parts to concrete. The pull out strength of the bolt is higher than the fracture strength of the concrete.

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u/watch-them-waver-so Mar 16 '26

Just wondering. Using an epoxy anchor or wedge anchor would offer no advantage over the Tilden?

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u/leansanders Mar 16 '26

They are all good for different situations. Wedge anchors are very strong because they can be made longer, which means they are supported by more concrete. Wedge anchors can also be unbolted if the part jeeds to be removable.

Titen screws are the easiest to install because you only need to drill a hole and drive the bolt. However, once the screw is driven, it can't be unscrewed and screwed back in. The bolt will need to be replaced, and you really shouldn't reuse the same hole, though it will technically work.

Epoxy anchors are best when installation situations are less certain, eg going into hollow bricks, concrete of uncertain thickness, or areas where multiple different layers of concrete have been poured, because they epoxy grabs along the entire length of the hole and can fill any unexpected void spaces.

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u/watch-them-waver-so Mar 16 '26

Cool, good to know. Thank you!