I’ve always liked the idea of a little cabin that, while looking rather unassuming and generic, is actually made of a highly resilient material like concrete. I’ve always been fascinated with this product made here in Montana. But, sometimes, for non-residential uses such as secure storage, you don’t really need a nice appearance. And while I have seen plenty of thick-walled concrete structures, the roof is always the weak spot. It seems like you never see a non-flat concrete roof. So, I was surprised to see this in my travels today:
Its a concrete building, about the size of a small cabin, that is used by a local utility for some purpose. But what catches my attention is that the roof is a big slab of concrete. Many concrete structures don’t have concrete roofs…making the roof the weak spot. This baby, however, is delightfully 100% concrete. Forest fires are no problem around this thing.
My use? If I had a place out in the sticks, I’d love to have a place like this as my ‘shed’ where I’d keep my goodies. Trick it out with a more reinfoced entryway (or, better, a hidden tunnel access) and I’d feel pretty happy knowing my stuff was secure.
For a more stylish look, theyre doing amazing things with concrete panles and pouring these days. This one is one of my favorites.
But, for now, I’d settle for a nice chunk of middle of nowhere with a nice concrete building on it like the one shown above. Gotta keep playing that Powerball.
A former co worker went ICF and 18” of concrete then put siding on it. Kind of speedy but if you want a normal looking house that will stop a .50 BMG it’s a legit option.
I’ve considered a flat concrete roof with a metal roof over the top of it, some places in the islands they do that for hurricane purposes.
I was at a commercial facility where they had a clamshell style hangar set up for storage and a misting system on the roof to help cool it. I’ve pondered if a system like that and a metal roof alone could get the job done.
Not as good as concrete admittedly but much easier to retrofit.
I built a small shed/cabin using Starplates and then ferro cemented the whole thing including the roof.
Check out http://sollarsshell.com/
Even concrete crumbles if exposed to the intense heat of a forest fire for long enough. Concrete and adobe houses in the Oakland hills were destroyed in fires there several years ago. So – concrete house with cleared defensible space around it. Not exactly hidden in the forest.
I’m impressed with Sollars!
Some years back a friend had a set of plans for a building that had walls composed of cabled-together flat concrete panels – haul ’em in on a truck, crane ’em into place, anchor ’em to the slab, string the cables through and tighten, a little like how post-tensioned concrete is done. The flat roof was simply the “generic” cast panels used in commercial parking garage construction. Ugly, to be sure, and in dire need of some sort of decorative pitched roof, but it looked pretty damn solid and about a fireproof as you could get. Turned out tilt-up was easier and cheaper for what he wanted beause it allowed for longer and taller wall sections.
The concrete roof idea could be implemented easily.
It would appear that all one has to do is to reproduce
the manner in which high rises are fabricated.
Metal beams, then a layer of metal sheeting, then
they pour the concrete.It sounds fairly simplistic.
And quite possibly I’m over looking a part of the
process, but it couldn’t be much more to it than that.
Just scale the materials to meet the size of the project load.
It might be a good idea to cover it with a layer of metal
roofing material…just to minimize eventual weathering.
Yes, concrete will weather unless sealed or covered.
The sealer will only hold up so long under the harsh UV.
OBTW – exposed concrete and it’s dust does cause cancer.
Pour fluid on a slope? High rises pour flat/level floors or formed shapes(foundations/steps). A tile roof(spanish mission style)would be ideal.
Any contractor who builds hurricane construction(Gulf coast) could build either of those in a day or two with a few weeks of lead to pour panels and arrange transport/crane. The difference would be the machine that twists the rebar together to lock the hurricane proof together and the requirement of 90deg. turns at doorways to prevent wind blowing out doors. This would not be safe during forest fire,the heat and lack of oxygen could cook and suffocate anything inside. Looks pretty bear and swat proof.
My house’s walls, foundation, and basement are reinforced concrete, the roof is metal with insulation sandwiched between the metal and an inch of plywood substrate. The joists are all hurricane strapped to eye bolts sunk into the top of poured wall sections ( we tend to get tornadoes).
Pretty happy with that, about 2100 ft not including the garage or basement. Cool in the summer, warm in the winter. What’s not to like? Looks like a normal Hacienda style house. Bought it for a really good price after it languished on the market since the locals wouldn’t touch it because it was “too strange”. Hey! Their loss… Would highly recommend the building method.
Regards
My brother in law built buildings like this for the forest service in NE Oregon.
I can’t remember the wall or roof thickness, but the footing was 2’ thick with rebar every 4 inches in any direction. The concrete had to be rated really high ? (Something about psi rating, or crush rating or something) They were always taking samples) They’re built to withstand just about anything nature can throw at them. Falling trees, cat 5 winds, snow loads, etc.
he made pretty good money building those.
If you haven’t seen this guys concrete castle in upstate NY, check it out. Very impressive and he’s got a lot of other fun projects as well.
https://www.youtube.com/channel/UCUujfNBK9uv3cIW-P5PX7vA
Andrew has alot of interesting vids.
while you can build a building that’s bullet proof your weak point will always be securing the entrance. Back in 1978 I was involved in installing new cut proof and jimmy proof hinges,hasps and locks on Air Force nuclear weapons storage bunkers. They couldn’t be cut with a portable saw but We could cut right through them with oxy acetylene torches. Their purpose was to delay entrance for a few minutes till the guys with rifles and machine guns could show up. If you can construct your entrance to have the hinges, hasps and locks protected you can keep most folks out but the guy with a torch will be a problem.
Gentlemen that’s why castles have overhangs and murder holes to PROTECT that Door-Gate. All defense with out offence means your in a tomb.
Also if your spending that level of effort and money remember it’s a stupid rabbit that has only one hole in his burrow to free with.
No fortification can withstand an attack if it’s not actively defended.
For an occupied structure, lay it out so that there are no points on the exterior that can not be covered by fire. Put the entrances where they can not be rammed — think SWAT armored car with a ram extension on the front — and configured so that any one entering will come under fire from multiple directions — including from above if possible. The simplest option is probably an”‘airlock” design featuring two front doors: an exterior front door of fairly normal appearance, that opens into a hall that runs parallel to the exterior wall and then turns 90 degrees to the interior front door which is as solidly built as possible. Impossible to ram, and a confined space where attackers can be dealt with as you see fit.
The designs of medieval castles offer many useful ideas. ‘Murder holes’ for example.
All this takes up a lot of interior space that then becomes less useful. The “airlock” hallway can make a handy mud-room at least. Plumb in a utility sink and a drain in the floor.
Why not just go with concrete CMU block for the walls, and save the roof for your concrete panel ? I you like, you can grout the wall cells to make them solid.
Look at USG STRUCTURAL PANEL CONCRETE ROOF DECK for reference. One and two hour fire rated. Steel bar joists or other steel shapes to span between the walls.
This decking is NOT WEIGHT BEARING for the record. So for snow fall, this material requires some roof pitch to rid it from the weight.
Windows and doors seem to be a week point. I put a steel door that opens outwards on my garage (and no windows), seems to be the best way to construct for the lowest cost. Still it would be very hard to prevent entry to a determined attack unless one were home and the M1A was ready for service.
These homes survived the California fire storms.
https://logixicf.com/blog/insight-and-advice/surviving-wildfires-with-homes-built-with-insulated-concrete-forms-icfs/
The simplest solution is a flat concrete roof poured in place, with a lightweight metal roof over that to shed rain and show and provide environmental protection for the concrete roof. Could even be built by just a few people and a small on-site mixer though I would not want to have any part of the labor involved in that.
We built our cabin with metal siding and a metal roof, in addition to being low maintenance it also is not particularly flammable. We did build an approximately 200 sq/ft room surrounded by 8 inch thick reinforced concrete walls on the uphill side of the walkout basement though. Its a nice feeling pulling up the hidden 500lb vault door to step inside.
pre cast might be the route to go. https://precastbuildings.com/products/precast-concrete-utility-shelters might want to think about subsurface and mounding top soil to create an 560 degree concealment and thermal protection.
1a) The proper way to do it is to bury the building/structure, including making sure the roof is stressed for several feet (3′ or better) of sodden earth, plus snow load as applicable, and a reasonable weight of vehicles, unless you’ve chosen a slope where vehicle access is seriously unlikely. Having an M1A2 or CEV suddenly come crashing into your living room ceiling is always a bad day, in many ways. This isn’t as hard as it sounds, especially if you get your hands on the US Army Field Fortification Manual circa 1940, in which they completely illustrate the then-world’s best bunkers from WWI, capable of defeating direct hits by all known artillery and bombs (way bigger stuff than most of what we use now, btw), when the pinnacle of construction engineering was 200 privates with picks and shovels and sandbags, and some timber framing. Steel-reinforced concrete is orders of magnitude better than that, BTW.
1b) A (IIRC) 4000PSI pour is waterproof, and what is used for pre-cast sewer pipes, culverts, etc. Water inside an underground facility is never your friend. Waterproofing the exterior side of walls, digging underground French drain gravel drainage culverts away from and downhill from the site, and throwing down a pond liner over the roof of the whole thing before you cover everything with earth is not too much insurance of a warm, dry hobbit-hole.
2) In a large enough building, you make the ventilation sealable from inside. There’s enough air in a building that size for multiple people for a full day or more, without risk of asphyxiation. There is nothing on the earth’s surface that’s going to burn full-on for 24 hours, short of the eruption of the Yellowstone Caldera, or the earth falling into the sun, in which case, you’re pretty much screwed anyways.
3) Like good German bunkers on the Western Wall circa 1944, the entryway is to be covered by a dedicated anteroom accessible from inside the facility, 90° offline on one or both sides of the main entry, which allows putting any jackhole using a torch, or any sort of entry stack, squarely in the kill zone.
4a) If you’re planning on covering the entry by fire literally, using an XL-18 flammenwerfer, go to the head of the class.
https://throwflame.com/products/xl18-flamethrower/
Fire is the Devil’s only friend, but it’s yours too, if someone comes calling uninvited. And people running around and exiting the entry point screaming and on fire tends to discourage any subsequent attempts. I’ve heard.
4b) The ability to rapidly flood an entry tunnel with H-bottles (9″ dia. x 52″ height)of NO2 or CO2 works also, because would-be intruders generally can’t breathe in an atmosphere that pushes out all breathing oxygen, unless they’re wearing SCBA or pony bottles, which is already a limiting factor for them. In which case, revert to 3) or 4a), above.
Bonus: People dispatched by sudden asphyxia are absolutely silent, there’s no messy chemical residue from inert gasses, and they leave no messy bloody bullethole residue nor crispy critters to clean up afterwards, and in more sedate times they become a handy resupply point during any respite in the siege, once you ventilate with normal air for a few minutes.
Just saying.
5a) If you have a sense of humor, a solid block of concrete 8’x8’x8′ or so above-ground, with a conspicuously-placed solid steel faux entry door, complete with reinforcements all over the inside set into the concrete block when it’s poured, to give people something to futilely pound on, shoot at, blow up, cut on, etc., for a few hours, is always both practical and funny as hell.
5b) If you choose to double you fun by covering 5a) with some of the goodness of 3) and 4a), above, so much the better.
6) A sliding tunnel-sized block of concrete that plugs the entryway from access once you’re inside cuts way back on shenigans from lesser-motivated visitors.
7) You always have more ways out than people can find in.
Always.
8) Including ways out that conceal more ways out, and set people intent on finding you to run off and about the countryside chasing their tails. Careful study of the VC Tunnel Masterclass materials -Worldwide Silver Medalist Winners at Hide & Go Seek- at Cu Chi is strongly recommended.
9) Plan for the worst you can imagine, then go beyond that.
If you anticipate that they’ll be willing to use Arc Light with JDAMs, ADMs, and/or chem/bio-weapons to dig you out, or finish you off, you’re pretty much already screwed, aren’t you?
But if you can sit inside and laugh while a horde of zombie cannibal bikers tries and fails to gain entry for a week or more, you’ve pretty much won the round.
If you built 5a) with an entry to Nowhere In Particular, including both 6) and 4b), such that it becomes a re-useable roach motel for determined would-be entrants, well…it sux to be them, doesn’t it?
And yes, I’ve got quite a graph-grid notebook of serious annoyance for modern-day besiegers. And I take my privacy pretty seriously.
Are you my long lost brother? I was just going to post that one should study the the defeat of Fort Eben-Emael, the defenses at Point Du Hoc, and the rolling over of the Siegfried Line. (Interesting to note, Eben-Emael is now VERY pixelated on Google Earth, last time I checked it was still in high-res.) You have posted some ideas that I’ve had for home defense for a while, particularly 2, 3, 4 and 8.
I have found it helps to play some table top fantasy RPG’s and design your own “castle” then let players try to destroy it, improve and try again.
No.
Just a guy that thinks that video of the cops in some E. European sh*holia where they gave up to no-knock some dude’s door wasn’t funny enough.
I want anyone attempting uninvited entry to be so shell-shocked that afterwards, they decide the best course of action is to ignore me and just wait until I die of natural causes.
A concrete roof in an earthquake zone seems like a really bad idea…
1M miles of freeways, including overpasses, in earthquake zones, less than 1% of which failed in 7.0 earthquakes, would argue that’s not as big a problem as you think.
Anything that gets built half-@$$ed is always a bad idea, but application of proper engineering works every time it’s tried.
The people who bought those surplus nuclear-hardened aboveground communication facilities from the phone co. and fedgov in the last 2 decades have the sorts of concrete aboveground bunkers Cmdr. Zero was after, with a bonus of space inside. And generally with clear fields of fire 360° around to the limit of individual weapons range, and usually a handy perimeter fence.
I just think having something a bit more modest, only not visible for miles, because buried, is a bit better option.
That is why I don’t live in one.
If you are that worried about it, put it on springs. That is what is under the complex in Cheyenne Mountain.