How to build an underground shelter?

Don't ask me why, but I have this urge to build an underground shelter. Not only would it be a good thing to have for my family and I, but it would also be a fun project nonetheless.

Can anyone help me out here and maybe direct me towards some good information that would help me accomplish my goal of building an underground shelter?

We have a basement here in the house, and I would love to dig right in the basement, but that's not going to happen, specifically because the basement is finished and in very good condition so I'm not about to tear it apart. However, we do have a small amount of land in the backyard which I could easily tear apart and make some sort of underground bunker or shelter.

I'm aware this wont be an easy task, but I feel energized to do it and a need to as well. Plus it would be fun I think, I already have ideas planned out in my head, I just need to put them on paper. But before doing so I was hoping someone could provide me with some links or some personal advice on how to build one, where to start, what supplies I'll need, and what supplies to include etc... So if anyone can help me out I'd appreciate it.

We have had a couple threads on this very subject recently.

www.abovetopsecret.com...

www.abovetopsecret.com...

Lots of very good information.

Get shovel

Dig

Check depth

Dig some more


Rinse...repeat



(Sorry - had to :-)

I've been looking into underground shelters for a few years, and I have a few suggestions.

1) Do a LOT of research first...
By that, I mean THINK before you make any irreversible decisions. Think about whether or not you want a contractor to do your work for you, or if you want to do it yourself. If you hire a contractor, it's gonna cost you, and they're going to put that thing wherever you TELL them to put it. Which may not be the BEST place, right? If you build it yourself, on the other hand, you may not be following safe and sound construction techniques. You need to READ a LOT, and RESEARCH underground construction techniques, or else you might be building a death trap, okay?

Believe it or not, some of the really old issues of Popular Mechanics have GREAT home-brew bunker plans, which were very popular back during the Cold War. You can find underground bunker plans on Ebay dating back to the 1950s and 1960s — I've purchased a few, in fact. Aside from that, try Googling "Underground Bunker Plans" and just MARVEL at the results.

2) Examine your property for the best location...
First off, building in your basement probably is the worst idea. Let's say we actually have a nuclear strike, or a major natural catastrophe such as a hurricane or earthquake or volcanic eruption — your house could collapse, right on top of your bunker. Many, many TONS of rubble, right on top of your bunker. It's a death trap.

Build out in the open, and not near any tall structures. Build out in the open, and NOT underneath any large trees... Same reason. If a big oak tree comes down on your bunker, you could be trapped or worse. Also, large trees have immense root systems, and growing root systems can compromise and even penetrate an underground structure — even a structure reinforced with steel and 2 feet of concrete. If the structure is penetrated, it'll flood. Count on it.

Observe your property for about a year, if you can wait that long, and WATCH for areas of flooding, as well as areas that never flood. DO NOT build in an area that floods regularly or that takes runoff from adjacent property. Again, I don't care HOW sturdy your underground structure is, water finds a way to penetrate it. Every time.

3) One of your greatest concerns should be ventilation...
Underground engineers have known for centuries that ventilation is the difference between life and death. Back in the 19th Century, railroad builders discovered that the BEST WAY to cut tunnels through mountains was to dig two tunnels, side-by-side, one for the railroad itself, and one tunnel to provide ventilation. This innovation saved countless lives and it's a technique still used to this day.

As this pertains to underground bunkers, you must think in terms of two separate ventilation systems to provide a flow of fresh air through your bunker. You can certainly disguise your ventilation ports above ground (and we can talk about that later in the thread), but you need 2 independently functional ventilation systems in case one is disabled somehow.

Once you build the bunker and get in there, you have to check both ventilation systems regularly to make sure they're open and permitting the free flow of air. This is especially important if you're thinking of a filtered ventilation system capable of preventing toxins into your bunker.

Anyway, there's a LOT to think about before you begin, including how you intend to dispose of sewage and bring in fresh water, among other things. Let's hope this thread generates a lot of good suggestions.

— Doc Velocity

Doc has some good stuff there, but there is a lot more to it then what he is mentioning above. You need to check the water tables, or your bunker will unbury itself, leak, or deteriorate. Water is the biggest problem with building anything in the ground. If there is too much water around the structure, it can actually enhance the shockwave of an explosion, and be a death trap rather than a safe haven. Underground structures that are not correctly insulated will have problems with condensation constantly forming inside them, and will become a flooding, mildew ridden, mess of a fungus farm. You need to have proper drainage and a footer, just like the basement in your house. It’s been awhile since I took basic architecture, but a footer looks something like this:
[atsimg]http://files.abovetopsecret.com/images/member/bc6d43109d89.jpg[/atsimg]
If you do not know how to pour a footer or a slab, you will need to hire a professional to do it for you. It can be somewhat complex, and even I would not attempt it.

Then you have the issue of just digging. You cannot simply dig a hole in the dirt then start building. The first good rain you have it will be a muddy hole in the ground, and if you have not protected it right, it will collapse into itself (hopefully not while you’re in it). There are underground lines, gas, electric, water, sewage, possibly even a drainage field for a septic tank or a sprinkler system. You hit a gas line, or knock out half your neighborhoods power/water, you’re gon’na have some splaining to do to the authorities. You need to make sure that you are not building on an easement. You need to ensure that you have the rights to dig past a certain depth, I.E. you have the mineral rights to the property. Believe it or not, you do not own the ground beneath your feet all the way to the core of the earth any more then you own the sky above your house.

Then you need the permits to build, and you have to build it according to code. If you start building, and you do not have the right permits, they can make you remove it. Nothing would suck more then to have the authorities show up, condemn the structure, and make you dig it back up, after you have invested tens of thousands of dollars into building it. Professionals will not touch such a project with a 10 foot pole unless you have gotten the proper permits. Again if you hire a professional, they should take care of all this for you.

BTW, building a fallout shelter is a whole different ball of wax then building an emergency/storm shelter. With fallout shelters you have to worry about a lot of additional stuff that you can skip on a storm shelter. You need to worry about the shockwave, over pressurization, radiation shielding, EMP shielding, and fallout filtration in the ventilation system. Really good shelters have multiple escape tunnels or “dig-outs”, decontamination/lockout room(s), pressure release valves, multiple filtered ventilation systems, climate control (it’s going to get really hot and stinky in there after a few weeks), generators with underground fuel storage tanks, underground water tanks and/or an electric/hand pumpable well, septic tank with drainage field, hydraulic door clearance rams (to clear debris off the upper hatch), a seriously heavy duty door locking mechanism, EMP shielding, and packed layers of different shielding material (so many feet of gravel, so many feet of packed sand, so many feet of clay, so many feet of packed dirt, so many inches of lead plating, etc). It can be QUITE expensive to build such a place.
You can get some prefab ones that will allow you to skip on much of the self construction, but again they are not cheap:

Utah Sheltering Systems
Hardened Structures LLC
Safe Castle
Alpine Survival

Thank you for the replies. You both definitely brought some things up I didn't think about, which I'm glad you did.

I really don't have the money to pay someone to do this for me, but I have experience with some of the things needed to make a shelter, and for the things I am not good at or don't have experience in, I know someone who would help for free more than likely, so that's a plus.

I'm going to try and choose a location that would be best. My backyard is not big (although past my property is a large field which I wish I could take advantage of). The yard works out nice though because it's built sloping down just a tiny bit (sloping down going away from the house), which means the water catches at the end of the property line, and not on the property itself. We have never had a flood, even doing large hurricanes the house was fine (other than some little damage to the siding and such).

reply to post by highlyoriginal


I recommend looking into this company:
Utah Shelter Systems
Their shelters are preset with most of what you need, ventilation systems, over-pressurization valves, duel escape hatches, you name it. They run about the same cost as a SUV, around the $40-$50K mark, and from the sound of what you are describing will fit what you are looking for:

Utah Shelter Systems
Complete Shelter Includes: One 36-inch diameter entrance with 90 degree turn and horizontal and vertical runs; one 48 inch diameter entrance with 90 degree turn and horizontal and vertical runs; two hardened blast doors; 6-inch diameter steel intake and exhaust air-vents to surface, with goose neck turn at top; two ladders; complete floor system with removable center panels; AC & DC wiring system with DC light fixtures; ANDAIR VA 150 air ventilation and filtration unit (177 cfm unfiltered & 88 cfm filtered); end plates painted with epoxy rust inhibitor; white on inside surface of shelter body.

You can, of course, add features later on, as well.
The shelters are made from steel tubing, which not only provides effective radiation/EMP shielding, but is stronger than a cement/cinderblock structure. They can place the shelter under your driveway, and run one of the two routes into your garage and/or basement:

If your yard has mature landscaping, sprinkler systems, or large trees, you may want to consider placing your shelter under your driveway, and accessing one entrance from inside your garage.

reply to post by highlyoriginal



keep in mind that there may well be more devestation underground than above...

Look up a book called "How to build your own underground home" by Ray G. Scott. It's got a bunch of explanation and photographs and stuff. I haven't tried to build anything out of it, but it looks useful, and has some good ideas. It might be available online in pdf format somewhere.

reply to post by defcon5


I would love to buy a pre-made structure, trust me. But I don't have the money... it may be possible to get the money in the near future through if somehow things end up going very well for myself and my family (unfortunately I don't see that happening too soon though).

I'm trying to build this at my parents house, the under the driveway thing actually sounds like a decent idea, although I wouldn't really want anyone to see it being put in, and the house is in a neighborhood.

If my father ends up selling his business, then we could possibly go with a pre-made structure, however I still wouldn't mind having this project to do ourselves, I would enjoy doing it and yes I know it will be hard.

Thanks to everyone for the replies.

You should still look through that site, they have a lot of good information, much of which comes from the Swiss Civil Defense Bunker Program:

CONCRETE SHELTERS:
Swiss shelters for private homes must are built to a minimum code of 1 atmosphere (15 psi), and government civil defense shelters are built to a 45-psi code. Military and critical mission personnel in Switzerland are assigned to heavy blast shelters in the 200-psi plus level. Please take note that our ‘All Hazard’ steel shelters, if installed correctly, also protect to the 200-psi level. We believe these Swiss codes should set the standard for shelters in the United States.
…
People in America mistakenly believe that shelter ceilings and wall slabs of an 8-inch thickness will protect them from the effects of radiation and blast. They have been misinformed. Eight inches of concrete, with no building overhead, will give a radiation PF of less than 8. Even in low radiation risk areas, this level of protection is not adequate to save lives. The accumulated dose for one week would reach between 300 rads and 600 rads, with an expected probable death rate between 50% and 100%. The minimum blast and radiation requirement, with no building overhead, is 22 inches (see chart below).

Shelters built under a building, however, have an automatic PF of approximately 15, because of the mass of the home and roof above. An eight-inch slab roof under a building will give a PF of about 100. People in low to medium fallout risk areas will most probably survive with no symptoms. People in high fallout risk areas, however, will receive about 200 rads, with some deaths. They will also be expected to have an 11% increase in survivor cancer deaths later in their lives. This concrete level does not meet the 14-inch minimum blast and radiation requirements for shelter slabs under buildings.
The following are the minimum concrete thickness for Swiss standards of 15 and 45 psi.

ETC…
There is a lot more on there then what is on the side bar, its sort of hidden at the bottom of each page. Just keep hitting the next page button at the bottom.

You're in Philly according to your profile location, which presents a number of problems. First off, the last time I was in PA the soil was mostly clay, which is terrible for building a shelter as it provides no drainage for water. Secondly your area is not a good one in the case of either a major earthquake or possible fallout as a result of a war…

Maps from FEMA/USGS:
[atsimg]http://files.abovetopsecret.com/images/member/97cec57edab5.jpg[/atsimg]
[atsimg]http://files.abovetopsecret.com/images/member/592b431db3e0.jpg[/atsimg]
[atsimg]http://files.abovetopsecret.com/images/member/84d068bce2ca.gif[/atsimg]
On a lighter note, being in mountainous terrain you will not have to worry about tsunamis, hurricanes, or large tornados...

Lots of Mines in PA that would offer much greater protection then anything that you could personally build in the case of war or disaster (well other than an earthquake, that is).

reply to post by defcon5


Thanks for supplying those pictures/maps. I am right outside of Philly actually in the suburbs (only about 20 minutes away from Philly though) so I do have some different possibilities for building and such.

My yard, from what I know, is not mostly clay, although I wont pretend to be an expert here, but from all the building we've done at my house, and around it there hasn't been any trouble so far. Also, I have no problem with buying some soil and replacing what I currently have in the area the shelter would go.

After looking at the pictures you provided, it does make me realize that I will need a thick shelter roof, and I already have a shed on the premises with the required codes for building and such, maybe I can move that out of the way, build the shelter under there, and then place the shed back on top with an entrance way coming up from within. The best part is it could be hidden within the woodwork on the floor, or a mat/rug could be placed down to cover up any sort of entrance hole. So if people come picking through the shed, the hatch from the shelter would be semi-protected.

Once again, thanks for the info.

reply to post by highlyoriginal


I to am around Philly. I’m about an hour away.
If I hypothetically were to build an underground shelter and was going to do it on the cheep. I’d buy a cargo container and just burry it and add stairs and ventilation etc. You can get used cargo containers very cheep these days, under $1500.00 due to the lack of demand from the recession.
I’m a contractor, so just a word to the wise. If your located in the Delaware county area watch out for the building inspectors. Out my way were a little more secluded.

Definately check into your Local Building Code and get the right permits to build this on your land, I know it sucks, but I wouldnt want you to get into legal troubles

reply to post by xynephadyn


I know, that is my biggest issue. I have a shipping container I found that is right in Philly for sale, it's actually 8'Wx9'Hx40'L and it's only $1550.00! That is perfect for what I need, and it's plenty of room to build some beds and storage space, plus room for ventilation equipment and a water filtration system - I'm really looking to hold approx. 4-6 people so this would be great.

Permit wise, I really don't know what exactly to ask for, and I really wish I didn't have to get permission because then they are going to be aware of my little underground 'lair' But I will do what it takes to do this properly as to not get in trouble and end up having to dig it up.

Can anyone point me in the right direction of what I'd need to ask for permit wise?

reply to post by highlyoriginal


I assume that I'm permitted to post this link, but some forums are particular about such things, for good reason. If it's against the rules, I apologize.

highlyoriginal, you might start here: webapps.phila.gov...

reply to post by Beinion


Thanks for the link, I appreciate it.

I am actually located next to Philadelphia County, I'm in Montgomery County (which is still about 1/3 or more of Philly). Funny Philadelphia County doesn't cover the whole city, just part of it.

But anyway, I will need to check out what my township thinks of my idea as well, they are a bit hard on everyone here. It was actually a bitch just to get permits for the shed... so I hope I have some luck with trying to get a hold of some for building something underground.

reply to post by highlyoriginal


You're welcome. All I did was Google "Philidelphia building permit" and follow a few links; the top link on the Google search led me to the link I provided for you. I would think that it would work similarly if you simply put in " building permit".

reply to post by Beinion


I did do just that after I saw your post, and I found the Montgomery County website and emailed the correct people asking them what permits it would take to build an underground shelter. I tried to be general, but give enough information that would help me figure out costs and such.

I'm still waiting for a reply, if I don't get one soon I'm going to just call them, but I feel sort of uncomfortable calling and saying "Hey, I'm going to build an underground shelter, what permits do I need?" I feel like I'm going to be laughed at, but then again who really cares?

Does anyone have any advice on what I should say so I don't give out too information but I get the required permits? Maybe someone who has done this will be able to help me.

Check with your local city planning and permits office, likely located at your city hall, they should be able to point you in the right direction