Storm Shelter design, Thinking Out Loud

I've been designing a storm shelter / survival equipment storage room for some time now. It won't be totally bullet proof, but should be pretty resistant to flying 2 x 4's or debris.

Let me run this by you guys for your collective pondering and see what you think.

Here's the idea. I live in a 2 story sticks and brick home in the Country and have a wrap around porch. On the south side of the porch there is 16 feet long run of un used porch/as in no visibility or reason to be there. My Master Bedroom Closet is where that porch stops on the south side of the house. Beautiful view of the air conditioner units.

I'm thinking of expanding my bedroom closet about 6 feet longer to the edge of the bedroom window that looks out over the wrap around porch of the south wall of the bedroom.

This will give me approximately 6' x 6' more closet where I will build my safe room add on inside. In reality I will build the safe room on the porch first and then continue the house wall siding to cover it and blend in with the rest of that side of the house.

I will be using 8 inch and 10 inch wide, 14 gauge steel "C" purlins. My plan is to bolt the Purlins side edges together with the flat side out. Most likely either 1/2 in or 5/8th inch grade 8 bolts with washers spaced every 10 inches. The floor plates with be 3/16th thick structural in 3 x 2 inch angle. The 3 inch side of the angle iron will be the base that will be "Red Headed" into the 8" concrete foundation with 5/8" bolts.

The roof/ ceiling of the room will be "C" Purlins bolted side by side and to the roof angle plates. Then tied to the wall plates with 4"x 3 inch 3/16" structural angle iron.

Just so you understand, I live in an area where the largest tree is barely 12 feet tall and is more of a bush than a tree. I have 3 of these trees on my 3 acre property. I'm more concerned with wind and flying debris. And yes, I have worked Tornado damage before in my career. So I know what the possibilities are.

The beauty of this steel box will be it will all be bolted and drilled, with a jig for consistency, in my shop on a commercial drill press. And the nuts will be mig welded in place. The nuts will all be welded to 2 inch washers then the washers welded over the drilled holes to ease construction. The bolts will have lock washers the flat washers. All installed with an impact drill.

The 32" wide entry door will be in the end of the master closet wall, hidden behind the shoe closet. The entry door will swing into the box and be made of a minimum of 1/4" , possibly 3/8 " steel plate, welded to an angle iron frame. The door wall frame will be framed and welded and bolted to the "C" Purlins. Door latches will be like those of a safe or Submarine. Thinking I may hinge it like a Commercial airplane door with double hinges so it can be opened and folded flatter for easier entry.

The corners of the box will be 2" x 2" box steel with appropriate RIVNUTS placed in the same spacing and all the other bolt patterns.

This safe room will then be extremely fire proof insulated and for sound deadening and temperature insulation. Possibly with Kevlar panels if the cash holds out. The beauty is I could add Kevlar panels to the inside of the "C" later. The inner walls will be finished out with removable ECM or Wood Panels, screwed in place. This will also allow me to reconfigure the wiring or ventilation as I see the need.

I will wire in the room for 12 volt lighting, ventilation fans, Ham / CB & GMRS radios (with appropriate antennas mounted outside) and other 12 volts systems and use lithium batteries recharged by 2 - 10 watt solar panels mounted on the outer wall of the house on the south side. Plus a hand crank charger. And there will be shelving brackets everywhere so we can manage our storage anyway we feel we need. All wiring will be installed in conduits and wiring will follow Commercial Standards. I'm a Retired power Company Lineman/ Technician.

The plan is to add a fold down cot to the longest end wall. It will be used more for seating but will make a comfortable place to sack out if the need be. Since it's just my wife and I there won't be much need for more bedding. We will have a fold down computer desk table with a flat screen TV mounted to the wall. I am currently wiring the house for 12 volt security cameras with feeds to both my office and safe room. This will give me monitoring of the safe room charging system outside the safe room.

BTY, My wife is a Certified National Weather Service Storm Spotter! So she will insist on having her Ham Radio and Weather Radar in the room.

All 120 volt outlets will be fed from the house power system so we will know if the house power is still working. (I'm going off gird with solar panels and cisterns on the house, but will maintain back up connections to the grid.) Oh, and I already have a backup generator wired to the house wiring.

I have a DC 12V/ AC 120V dual zone freezer and hassock toilet for the safe room. Plus water and food storage.

Going to be cramped, for sure, but all my friends are Cops, so if our house is ever hit by a Tornado they will know where to look for us. So Hopefully we won't have to stay in it long.

If it goes as planned the safe room entry door will be hidden by the shoe shelving. And that shelving will be held to the door with removable pins that can be removed from the inside of the door, just in case the house has collapsed on top of the room.
But like I said, the rescue guys will know where to look for us. And most of my neighbors have either safe rooms or tornado shelters outside their homes. So not likely I will have people breaking down the door to get in. And yes there will be firearm storage inside.

Did I forget anything?

If there is an interest I'll add pictures as the build progresses!

Hell yes there is interest. That sounds very legit. The wife and I have been pondering building something our-self's. Just ain't put my finger on which way to go just yet...

Make sure the ceiling is high enough for you to stand erect.

BRD@66 said:

Make sure the ceiling is high enough for you to stand erect.

Click to expand...

Thinking of the wife, very smart.

About the only other thing that comes to mind is, drainage. Don't remember seeing that mentioned.

The walls of the house are 10 ceilings so it will be at least 9"6" height inside the room .

The wife is 5'4" tall and weighs in a 102 lbs. I'm 6'1".

Drainage? My house is on a hill at 900' above sea level and 350' above the nearest lake 25 miles away. (Eagle Mountain Lake) I'm not real worried about drainage at this time since our yard is domed and all water runs away from the house. Even the worst rains we've had only get 1/2" deep in the yard as it runs off. And my slab foundation is 8 inches above the ground level. But, that's something for people to consider if they follow my lead.

I had considered just erecting the walls inside the big walk in closet without extending it, but my guestimation would show we'd lose about 6 inches of wall clearance with the added wall thickness's and require the clothes to be moved toward the center at least 3 inches a side. And that would give us less interior shelter space, require us to share the room with clothing and such. So extending the end of the room it just made more sense, and would allow us to store our survival equipment in a separate secure place.

I know a guy who builds door for gun safes and storm shelter door that I may hire him to build my entry door and frame for me. Wouldn't be cheap, but it would be solid!

Sounds good. My father was a building contractor from the mid '40s until the '80s and also put in some "fallout" shelters in the 50s. They were basically big (6' dia. x 10' long) tin cans. He dug out a hole big enough to set them in then poured a slab on top. They had a "turret" about 2 ft. square that came through the top. He also used one for a deer blind.

IDK about above ground. The Jerrell tornado vacuumed the foundation up. Everything above ground was gone. I know the odds of such a big tornado is rare but still. I wouldn't want to win that lottery.

If I did a storm shelter myself. It's going in the ground.

2 cents

The one I mentioned above was "in the ground" with only a slab on top at ground level.

It sucked the grass out the dirt. Big wide trail of nothing left but the dirt itself.

They say shelter in place. You'd have a better chance running.

The pic I just added of the shelter doesn't really do it justice. When my father stopped selling them, he took the last one out to our deer lease and fitted it in among some trees. It could then be used as sleeping quarters and blind!

I didn't really see what you planned on skinning it with.

One thing they usually do is add solid concrete blocks between the studs to stop penetrations. Then inside and out are sheeted with multiple layers of plywood.

Do not connect it to your house in any way. If the house goes you don't want it taking part of the shelter with it.

Let me clarify the room is going to be 6'x6'? If so, then unless you are midget then its to small. I would go 6'x8', you might have to stay in the room longer than you may think and you do not want to be standing up the whole time

What gage are your purlins? I doubt seriously you need or will gain any value by using grade 8 nuts/bolts unless your building out ¼ plate steel.

Were it mine to build I would use metal for the outer skin and ¾ marine-exterior grade OSB for the inside, painted white. This will give you max interior vision with min of light (using LED's). In addition it will help keep the room at a even temp, cold steel is just that, COLD and in the summer can get REALLY HOT. This will mitigate temps and in the wild event of a cat 5 incident you might find the inner walls of OSB a little better to bounce off of rather than steel...

I was in Jerrell hours after their Tornado hit it! We were stepping over bodies clearing power lines for the Rescue Efforts and eventual rebuild. So I saw it. Lived it, still have bad dreams about it and other disasters I've been involved with. Spent 36 years fighting storms, airplane crashes and drunk drivers that you really don't want to hear about. Let's just say I was the guy the Fireman waited for before they entered a burning building!

And the Odds of a direct hit from a tornado is extremely rare. Most homes I saw there and at other Tornadoes had the roofs and a few walls ripped off. My box will be a 6' x 6' x 9' tall temporary shelter. Not meant be living quarters for more that a day or two at the most.

And it will be bolted to the concrete foundation, not the walls. so if the walls get sucked off the foundation the box should still be there. Saw the above ground, built inside the home, shelters in the Dallas Ray Roberts Lake area (Sasche???) take a direct hit and even though the entire house was GONE the shelters were still standing.
I have a lot of grade 8 bolts and I trust my life to them, so I see no need to go cheap on fasteners.

We have had tornadoes miss our home by a few miles more than once since we moved to the Country, but being a Wise County resident that's considered normal.

I was in a Tornado when I was 5 yo in Paradise TX . My Aunt took us to the root cellar where we hunkered down for about 30 minutes. When my Uncle open the door we looked out and the entire barn was gone, but the house was completely untouched only 100 feet away. The root Cellar was between the two structures.

You can plan and prepare for every worst case scenario, and never need any of it. But it's all going to come down to taking your best bet!

As for the steel, it will be 14 gauge steel, flat side out, but the interior will be insulated and cool white paneling over ECM for reduced lighting. If I feel the need I'll reinforce it with more steel sheeting on the interior walls and ceiling. But the walls will be almost a full 3 inches thick without the reinforcement. There will be a 2x4 wall studs covered in OSB Plywood, covered by siding showing to the street. It will match the house wall when done so it doesn't scream storm shelter. Hence the build inside the house walls.

Again, it's not supposed to be an end of the world fall out shelter for living in while the nuclear fallout is floating around in the wind. Just a safe room for passing tornadoes!

Guess I'll just have to get started on it and show Ya'll some pictures.

14 gauge is kind of thin. About a 1/16 of an inch. That ain't much.

Sent by an idjit coffeeholic from my SM-G892A using Tapatalk

If I'm picturing everything right, that 14 ga. will do the trick.

If I had a choice between above ground or below....I would choose below.....

However, I have heard of safe rooms that survived both tornadoes in Moore Oklahoma....

If you are working with 14 ga (5/64 ths) using Grade 8 bolts is a waste of money, no gain!

I would use diamond plate steel in 11 ga (7/64) or flat sheet in 10 ( ⅛ th). Where you bolt down the box to your pad and the main vertical and horizontal structural supports of your box you can use the grade 8, the rest grade 5 will more than do what you need.

If it were mine I weld up my frame if possible and bolt the rest to it, its the frame that will keep in place and the structure sound in a catastrophe.

While you may only spend minutes in your box as the tornado will pass quickly it may be that the roof has blocked you exit, so you may depend upon help to get you out, that help may not arrive until the day following so the 30 or so min you thought you would spend in there has become an over night stay...plan on it and you will be ahead of the game and far more comfortable.

For those who say 14 gauge is too thin, here's some light reading for you.
https://www.fema.gov/media-library-...709/FEMA_P-320_2014-ConstructionPlans_508.pdf

Matt at PFX Storm Shelters builds them, and he may be the guy I use to build my door.
His are really, really nice, but very expensive!

And yes, my exit door may be blocked by the structure, that's why the door swings in. And the room will have provisions to sustain us for a few days. You will notice Matts shelters are really small. Much smaller than mine. But I have firearms, so mine will double as an extra firearm safe.

Plus, my neighbors and LEO friends will know where to come look for us if my house is hit. I'm not hiding in a hidden, secret, bug out room that no one knows about. Plus we will have several different communication devices to call out for help.

This is not some half ass baked, alcohol fueled idea I thought of yesterday. After years of research I thought I'd share my plans with my fellow Texans. Mainly to share and also to find out if I missed anything new on the market. You guys want to go underground, good for you. Talk about trying not to drown! Underground shelters will need a lot of attention to keep from filling from ground water all year. And just remember, with an underground shelter you will have to run through THAT storms flying debris to get inside. Unless you plan on living down there every time the wind blows. And getting your exit door blocked is an even bigger threat.

If I were to build an underground storm shelter it would have 2 accesses. One from outside the house and one from inside the house. So if you are building a new house, consider that idea.

Also, our home is setting on top of solid rock, so digging through that would be insanely expensive. Ground water is 6 feet down.

I've been there and seen the real tornado damage up closer. A lot closer than I want to think about. We want something we can jump in once we see the tornado is going to hit. Like I said above, my wife is a Certified Storm Spotter, she will be looking for it, and advising the National Weather Service in Fort Worth where it is at on her 2 meter ham radio as it comes at us. Not likely a Tornado is going to sneak up on us. She has a neat connection to their weather radar!

I am more worried a tornado will change direction at the last second, than getting hit blind sided by one. So a speedy access safe room, inside the house, is more desirable for us.
Your needs may be different.

But that's why I posted my thoughts. So you can weigh your needs and take measures for your family. And I can get feedback about new stuff on the market.

With that, God Bless Ya'll!

You have to decide where your comfort level is with the odds. An F4 or F5 and that shelter won't survive. Anything less and you will probably be fine. Odds of an F4 or F5 are pretty small. Just depends on how you want to play it. Weigh the cost versus a buried shelter.

Yes, folks may know where to find you. But they may be out of town, injured or extremely busy. Give some thought to what you would do if the door was jammed. Don't count on any internet connections or anything requiring grid voltage. And your cell phone may not get much (if any) signal in there.