Very few people have built one but I am one that has and at the time I did not think to take step by step pictures and yet I took a few and will post them when I dig them out of a mislaid box of photos. I began the project by talking to a man in a city office who was in charge of cavil defense and asked him about what he thought about storm and bomb shelter construction as I wanted to build one. His counsel was interesting and that was to not get a city permit and construct it with as few people knowing about it as possible. He said if there was a war then you might find the neighbors fighting with you over it. Looking at the old civil defense plans my dad had saved since the 1960's it was obvious that plans would work for either a war or a storm, tornado etc.
I scrounge so this would save a lot; we built our own home after getting married and it was finished and ours in three years. So this project was no different. I always ask before I load up any thing that someone throws away so I have never had any problems. Look for what we need and start collecting. They were taring the store front off of a local outlet called The Popular and they had half moon window shades that stuck out over the sidewalk about 10 ft made of concrete and they pulled in a back hoe with a jack hammer attachment and went to work. Seeing the project I approached the foreman and asked about the cement reinforcing bar and he said I could have as much as I wanted but I would need to get it louse from the rubble and hall it away. This saved him from the labor costs and I soon had a lot of re-bar. I had a three legged plumbers pipe vice and used it to straighten out the re-bar and made a considerable sized pile. Actually way more than I would need for several projects beside this one. Bending the re-bar requires no special tools all you need is a piece of 1 inch ridged pipe about 3 ft long slid over the re-bar to the desired spot. Put your foot next to the pipe and lift the pipe. Re-bar protectors are very important as if you fall on the upturned re-bar in the foundation it can kill you. These are plastic caps and the investment is small compared to the safety benefits.
Near where I was working was a remodel job going on and I approached the foreman about some cinder blocks they were throwing away. He said to get a helmet and come back and I could have some. I talked to my boss and asked him if I could borrow a parking space and fill it full of cinder block. So I was hauling them as fast as I could go and as the pile was getting bigger and bigger the foreman could see value in the pile and decided not to let me have any more but I got nearly enough to do the job. It always amazes me the things that people throw away that are not valueless in tell someone else finds a use for them.
I had a cement mixer and so we could make our own cement and a place where I knew I could buy sand and gravel. Lumber yards discount broken bags of cement 50% so the trick is to buy the ones that are torn but have very little loss.
At the same place where I got the cinder blocks they had thrown away a floor drain that they had jack hammered out. This was old but useful as I wanted a floor drain. Since I lived in the desert this was as simple as digging in a piece of 16 inch cement pipe about 3 ft long just lower than the floor and leaving it hollow. This pipe was also discarded and most useful. A drain pipe was run to it and the floor drain was put near the opening. A scrap of plywood was placed over the pipe and the cement floor was pored over the big pipe.
I was driving across town on another day and found a plumbing company with hall backs from a remodel job of 6 inch ridged pipe and was able to buy all I needed for vent pipe for $45. Four inch pipe was what the job called for but the six inch worked fine.
There is a method of using cinder blocks called stresscrete. By sticking up the reinforcing bar from the foundation so it falls in the center of each hole of each cinder block the re-bar is then standing upright and the mortar is placed on the blocks below and the new block is slid over the upright re-bar and then set in position when the walls are to the desired height the support poles are put in place and a floor is built to support the cement that will be the roof. When this is finished the re-bar in the blocks is bent over and united with other re-bar to support the cement roof. Unlike normal cement work you do not want the re-bar to high in the cement as during a blast a huge section of the cement can shear off and crush the people inside, so the re-bar must be placed lower than normal.
The top hatch was made from scrap 1/8 steal plate from road side pickup. Scrap metal scavengers are plentiful in El Paso Texas and metal falling off of open top semi truck is just left with the drivers hoping that no one saw it fall off their truck as it would be impossible to get it back on top of the 10 foot tall side boards by them selves. I made a very nice lid with my chop saw hand grinder and welder in an afternoon. I had to buy the hinges. The frame was made out of 4X4 angle iron scrap I had laying around that I got in a bunch of other stuff that I used in another project.
We had very stable soil to work with in building a storm shelter that was full of caliche, so it proposed very little if any danger from cave in. But your choices of construction should consider soil type first and foremost as some soil is absolutely unstable and would need to be excavated at a 45 degree angle for your own safety. This would mean moving a lot more dirt. Concrete walls are more stable for a bomb shelter and stronger than stresscrete but stresscret is good stuff and works quite well for a storm shelter. This was not an expensive project in fact it was almost free but it was a labor intensive project. If you are afraid of work then you would want to consider hiring it done. I also pored the electrical pipe in place so I could have a light switch by the opening and a light over head and a plug near the vent pipe was laid in the blocks and connected to the electrical box where the light was overhead in-case I ever wanted an electric air pump. But in an emergency I would doubt you would have the electricity to power it so a hand pump would be better. After running the ridged pipe the electrical box is packed tight with old news paper and the box is securely screwed to the form. When the cement is pored and dry and the form holding up the roof is wrecked out the paper is pulled out and the screws inside the electrical box are broken off with a hammer and chisel.
Other things to consider if building a bomb shelter storm shelter and that is location and convince away from large items that could fall on the opening and trap you like big trees. Some like an escape rout as well. Water table is also a big consideration some storm shelters- bomb shelters must be built above ground. If you are going to invest in a storm shelter than why not have it double as a fall out shelter.
