Bunker...

[MedicYeti 96]

I have thousands of random thoughts floating around in my head, some completely unrealistic and some are possible. I have property that extends well beyond my back fence, just beyond the fence is a small hill maybe 10' high. I had the thought of temporarily removing 2 sections of fence and digging out a chunk of the hill in order to build a concrete bunker. In my head this would be maybe 15 X 30 then back fill the dirt and I'd have my own little hillside bunker with a heavy door. I could even make a section of the fence movable so this would be hidden. Maybe put a wood burning stove in there and vent it out the back of the shelter. I own property that boarders a freshwater pond so I could pipe in water and set up a filtration system. Maybe a composting toilet.

So, your with me so far.....

Now the reality, I know nothing about concrete and I know nothing about placing cinder blocks. I have extensive Lego experience but I don't think that counts. I drove a backhoe once thirty years ago. I do know a guy who would do the hoeing (is that a word?).

As I understand the dynamics I'd need to dig out the area then dig out an area to pour the concrete which would be deeper, thicker, around the edges to support the weight of the cinder blocks. I'd also need rebar (do I get that from the concrete joint?) a wooden outline needs to be made and level. I pour the concrete; can it be hosed in? I think I'd need 15 yards (according to some random internet site). The truck would not be able to get the the pour site, it would be 100 feet away. Then after this dries I'd start with cinder blocks (according to some random site I'd need 810 blocks). I'd have to mortar the blocks together then throw up some I beams to support the roof and use a corigated steel to support the roof and when the roof is poured the cinder blocks should be filled at the same time; or do they get filled beforehand? Would I create holes for vents and the stove in the roof before the pouring?

What type of concrete would I need?

Would standard cinder blocks work or do I need super blocks?

Do I need to put rebar in the blocks?

Am I completely crazy?

Is laying the blocks something one crazy person can do alone over time or do they need to be mortared (is that a word?) within a short time of each other?

How far do I space the I beams?

What thoughts do you fine folks have regarding this idea?

[Schrödinger's cat 87]

I have extensive Lego experience but I don't think that counts.

Best sentence of the day !

 

I can't help you about your questions, but I once heard from a concrete pourer that the area under your steps can be well fortified.

[djg0770 481]

You may want to consider a sea box instead...

[MedicYeti 96]

I did some looking into the sea box/shipping containers. I have found a number of stories of people who buried them then the walls collapsed. It sounds like the containers are made to hold vertical weight but lateral pressure is not something they are designed to endure.

I don't know if I could make a mold around one and pour concrete to reinforce it. I don't know if the weight of the concrete would be too much pressure for the walls.

That said, I could always clear out the area, place the container and not bury it. That would be a easier idea.

I've also seen stories of people burying school buses and that thought appealed to me. I don't know how that would turn out.

[Heavyopp 167]

If I was doing this, I'd bury a monolithic dome in the hillside --  

 

If I could get away with it now, without permits and the township getting involved -- I'd bury a monolithic dome in my backyard

[bhunted 887]

http://www.utahsheltersystems.com/

 

 

 

Sent from my iPhone using Tapatalk

[MedicYeti 96]

Thanks Gents. I've looked at the inflatable concrete, the Utah and Atlas and other shelters. My curiosity is about doing the work myself, the shelter companies charge a lot of money.

Is this something I could build myself and save money doing? Or is a project like this too far out of an amateur's skill set?

[T Bill 649]

Far beyond your skill set.  Find someone to design one for you and see what is really involved, You will be shocked.

[Schrödinger's cat 87]

IIRC FEMA has a whole list of requirements for a hurricane room like what thickness the door should be, how to make the wall, what material the door jamb should be made of etc. it may be interesting to you.

[45Doll 5,873]

"Fixed fortifications are a monument to the stupidity of man." George S. Patton

 

Do some reading on the Maginot Line. If you're in a fixed fortification, your opponent knows exactly where you are and how to either go around you or attack you directly. Anything built by man can be breached or defeated by men.

 

I admit I did consider a bunker of some sort at one time. But now it would only be for a transient event like a hurricane, not for long term survival such as TEOTWAWKI. Moving targets are harder to find and hit. But you do have to be prepared for mobile survival, which is probably harder.

 

So, depending on your purpose...

 

Addendum: here's a little life on the Maginot Line.

[Lambo2936 297]

I probably wouldn't try to do it on my own.. One screw up and your cinderblock walls are coming down on ya'... Cinderblock walls are ALSO not made to hold much pressure from the sides.... They'll hold insane weight from top to bottom, but smack em with a hammer in the side and they just fall apart to nothing (you should see what happens if a car taps the side of a standard cinderblock or brick wall..)

 

I Suppose it could be done.. You can only do a few courses at a time as the mortar has to dry, otherwise it would collapse under its own weight. I could see, maybe, burying a small shipping container and then putting blocks around it (rather than burying it in concrete and dirt). Between the two, it'd probably be much better off. You would want better-fortified doors, though, which could be done with some welding.

As far as pouring concrete roofs and stuff, it is ridiculously difficult and nothing i would suggest you do..
Concrete CAN be pumped but it is fairly expensive. We would generally just cart it in if it is a somewhat small job. If you're building an entire structure, then you can get a pump truck to move it to wherever you want. Never did anything huge, just pavers and such, so it was never an issue for me.

[MedicYeti 96]

Far beyond your skill set. Find someone to design one for you and see what is really involved, You will be shocked.

So my extensive Lego experience means nothing.

[CageFighter 236]

You may want to consider a sea box instead...

 

I dont suggest using a sea box, they are not designed to be buried.  

[Schrödinger's cat 87]

Lambo raises a good point. The concrete ceiling would probably be the most difficult part of the job.

[T Bill 649]

So my extensive Lego experience means nothing.

I was thinking more for hurricanes and the like, I don't honestly think the apocalypse is coming; and I'm a pre-tribulation guy so I hope to be raptured before the horseman arrive.

 

I got an approximate cost of $1,800 for the concrete floor and $1,300 for 820 blocks delivered. No door, roof or mortar prices.

I'm thinking this idea will be filed in the "That would be cool" folder and I'll move on to another idea.

I have seen people bury school buses, I'm not digging that idea.

I cannot emphasize enough the need to consult someone on the design.  Coming from a family that was in construction, your ideas are well mannered, but lack clear understanding of the scope of work,  As an example, you intend to set block on concrete slab, what anchor method, or you figure just setting them on the slab is enough?  Or, do you realize any where frost is present requires footings below the frost level to prevent heaving and subsequent structure collapse.  A structures weakest points start with a poorly designed and executed foundation, creating a future house of cards.

 

Do what you want, I for one would not be running in to save your butt, when it fails its intended purpose.

[siderman 1,137]

So my extensive Lego experience means nothing.

I was thinking more for hurricanes and the like, I don't honestly think the apocalypse is coming; and I'm a pre-tribulation guy so I hope to be raptured before the horseman arrive.

 

I got an approximate cost of $1,800 for the concrete floor and $1,300 for 820 blocks delivered. No door, roof or mortar prices.

I'm thinking this idea will be filed in the "That would be cool" folder and I'll move on to another idea.

I have seen people bury school buses, I'm not digging that idea.

Its fun to think about but in reality to do it right- which would minimize liability should it go bad- also figure in plans with engineers sign off, town permit fees- if they let you do it, excavation/backfill work, ventilation system especially with a stove, other interior comforts, a good mixer for mortor because a wheelbarrow and hoe sucks after the tenth time, landscaping around the bunker and to fix up your yard, maybe property tax re-evaluation......and the labor to finish or remove it when you quickly realize  you're in too deep. I get where you're coming from, I regret not building a "secret room" when I built my house and think about what could've been but back then was all about money and getting it done.

[EX Carnival man 223]

If I had the money I would look into one of these.   http://www.risingsbunkers.com/layouts-pricing-bunkers/

[BlueLineFish 615]

Most difficult part is the concrete roof. Ever see all of the rebar and support structure when they put a floor up on a high rise. Lots of support until the concrete dries

[302w 83]

Depending on what kind of span he is looking at he may be okay with q decking if he is only 6' wide.

[Silence Dogood 468]

I have thousands of random thoughts floating around in my head, some completely unrealistic and some are possible. I have property that extends well beyond my back fence, just beyond the fence is a small hill maybe 10' high. I had the thought of temporarily removing 2 sections of fence and digging out a chunk of the hill in order to build a concrete bunker. In my head this would be maybe 15 X 30 then back fill the dirt and I'd have my own little hillside bunker with a heavy door. I could even make a section of the fence movable so this would be hidden. Maybe put a wood burning stove in there and vent it out the back of the shelter. I own property that boarders a freshwater pond so I could pipe in water and set up a filtration system. Maybe a composting toilet.

So, your with me so far.....

Now the reality, I know nothing about concrete and I know nothing about placing cinder blocks. I have extensive Lego experience but I don't think that counts. I drove a backhoe once thirty years ago. I do know a guy who would do the hoeing (is that a word?).

As I understand the dynamics I'd need to dig out the area then dig out an area to pour the concrete which would be deeper, thicker, around the edges to support the weight of the cinder blocks. I'd also need rebar (do I get that from the concrete joint?) a wooden outline needs to be made and level. I pour the concrete; can it be hosed in? I think I'd need 15 yards (according to some random internet site). The truck would not be able to get the the pour site, it would be 100 feet away. Then after this dries I'd start with cinder blocks (according to some random site I'd need 810 blocks). I'd have to mortar the blocks together then throw up some I beams to support the roof and use a corigated steel to support the roof and when the roof is poured the cinder blocks should be filled at the same time; or do they get filled beforehand? Would I create holes for vents and the stove in the roof before the pouring?

What type of concrete would I need?

Would standard cinder blocks work or do I need super blocks?

Do I need to put rebar in the blocks?

Am I completely crazy?

Is laying the blocks something one crazy person can do alone over time or do they need to be mortared (is that a word?) within a short time of each other?

How far do I space the I beams?

What thoughts do you fine folks have regarding this idea?

 

The right way to do this is to hire a local mason who isn't overpriced to help with this.  Moving the crete 100' is no problem with Georgia buggies.  Pumped concrete would likely be more money.

It's a structure, so you're going to need permits, inspections, etc.  Oh, and by the way, block laying (and concrete placing/finishing) does take some skill, and it's hard work.  Concrete roof on structural steel deck isn't hard to do but it's going to cost you some money.

 

Yes, you need vertical rebar in the block (#5 @ 4' o.c. grouted in) - they get tied to vertical bars coming out of the haunched slab/footing.  You also need horizontal joint reinforcement every 2 courses vertically.  Lot's of other things needed, like parging/waterproofing, bonding the rebar to electrical ground, etc. etc. etc.

 

You'll need an engineer to lay out the roof, but steel deck (depending on the type) usually spans 5' - 7' or so.

[Silence Dogood 468]

I cannot emphasize enough the need to consult someone on the design.  Coming from a family that was in construction, your ideas are well mannered, but lack clear understanding of the scope of work,  As an example, you intend to set block on concrete slab, what anchor method, or you figure just setting them on the slab is enough?  Or, do you realize any where frost is present requires footings below the frost level to prevent heaving and subsequent structure collapse.  A structures weakest points start with a poorly designed and executed foundation, creating a future house of cards.

 

Do what you want, I for one would not be running in to save your butt, when it fails its intended purpose.

 

Nothing wrong with placing cmu on a thickened slab and starting the first course on that, tied to rebar.  It would be quite a bit more waterproof and economical if spread footings were used and the slab placed inside the walls, over the footing (typical basement construction).

[Budasac 13]

Just get one of these and call it a day.

 

Sea box / shooting range / safe room

 

https://youtu.be/okq6VIckNQY

[MedicYeti 96]

Just get one of these and call it a day.

 

Sea box / shooting range / safe room

 

https://youtu.be/okq6VIckNQY

Sorry. I got 1 minute into the video and I have made a few conclusions:

1. This dude got picked on a lot growing up.

2. This dude still gets picked on.

3. The dude has some shortcomings.

4. The brunette was possibly rented. If I had the money the dude has I'd consider renting a similar model.

I lost interest after 1:38.

 

Oh, something shiny.

[Budasac 13]

Sorry. I got 1 minute into the video and I have made a few conclusions:

1. This dude got picked on a lot growing up.

2. This dude still gets picked on.

3. The dude has some shortcomings.

4. The brunette was possibly rented. If I had the money the dude has I'd consider renting a similar model.

I lost interest after 1:38.

 

Oh, something shiny.

Yeah, I was going to add a disclaimer in the original post. The promo video is incredibly cheesy. The girl and car are just plain dumb. If you can get past that though, the product is pretty cool. They actually have a number of different models. I think that one is their "executive" or something. It's a neat concept. Basically a complete , self contained shooting range/safe room. They even make modular units so you can put them together to make them longer or add more lanes.

[tc556guy 0]

Thanks Gents. I've looked at the inflatable concrete, the Utah and Atlas and other shelters. My curiosity is about doing the work myself, the shelter companies charge a lot of money.

Is this something I could build myself and save money doing? Or is a project like this too far out of an amateur's skill set?

You're not just buying the product; you're buying their know-how and experience.

In the end. experience isn't free.

 

If you're truly looking for nothing more than a storm shelter, why don't you buy a drop-in pre-fab unit like this

 

http://pylesconcrete.com/stormshelters.html

[Newtonian 453]

Lego experience is very useful All my masonry projects except the patio are no-mud. But really a concrete/block roof is asking for trouble. I would not trust even an experienced mason. There's a reason they use wood for flooring. They don't even pour cement for bathrooms any more. Cost? Maybe.

 

Curious as to why you would want to do this. What kind of hazard are you preparing for? You can tell us. We've heard everything. You must be smart enough to know that when the torrential rains hit the structure will collapse. Ever see those ads for basement sealant? So it can't be for a hurricane. C'mon, what are you really doing this for? 

[MedicYeti 96]

Concrete isn't the way to go. Got it.

I know nothing about concrete and its abilities, which is why I asked so many questions in the original post. I would like a bunker for any kind of emergency, I live on a peninsula with 3 major roads out, I can easily get stuck. Storms, civil unrest, man cave, storage, eotw...... Who doesn't want a bunker, really?

I'm going to have to back-burner the bunker for another time.

I like the Atlas survival shelters but they are way out of my budget for now.

[Lambo2936 297]

Nothing wrong with cement/concrete. All homes in Israel are built like that, for obvious reasons. The bunker? Fuhgettabout it, the door was probably half a ton in steel alone, built to withstand some crazy direct impacts. The homes here would literally collapse at the slightest nearby impact haha.

 

A cement/concrete ceiling/roof is of no issue, itll just be really expensive.. tons of rebar work and such has to go into it.

[Lambo2936 297]

You're not just buying the product; you're buying their know-how and experience.

In the end. experience isn't free.

 

If you're truly looking for nothing more than a storm shelter, why don't you buy a drop-in pre-fab unit like this

 

http://pylesconcrete.com/stormshelters.html

That is a terrible design. In the event of a missile strike or the likes, that door can take a direct hit due to the angle. Also, any mild flooding would be an issue as that thing appears to be burried below grade. I believe 6k psi concrete is waterproof, but the door/seams may not be.