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A storm shelter can be your safety net during severe weather outbreaks. The following article will show you how to build one of these storm pits for yourself.

Things you'll need:

Form Lumber

Plywood

1/2" All Thread Rod

1/2" Nuts & Washers

1/2" ReBar

1 First you will need the storm shelter location spotted. A hill or a bank is good.

You will need a backhoe to dig down 6' or so and about 9 or 10' wide. You will

need to form up and pour your slab first. I would advise pouring a slab at least

8' wide, 10' long, and 6 inches thick. I poured mine 6 inches thick. I also sloped

it at about 2" of fall with a 2' X 2' X 4" deep drop down at the sloped end to hold

any water that might get in there. A sump pump in the drop down can pump any

water out, if that is the case.

2 Cut your 2- 2X6 boards at whatever length the storm shelter slab will be and

cut your other two whatever the width of the slab will be. Nail them together on

the ends making a square or rectangle. Then get it squared up by measuring

from one corner diagonal over to the other corner. Then measure the other two

diagonal corners. It is squared up when those measurements match.

3 Cut your 2X4 bracing boards about 24" long with a point cut on one end of

each one. You want to drive these in the ground up against the outside of the

storm shelter 2X6 form boards about every 3' or so so they don't bow outwards

from the pressure of the concrete. Nail your 2X6 form boards to the bracing

stakes. Then you want to go straight out from each one about 12 to 18 inches

and drive another one and then measure between those from the bottom of the

outside one to the top of the one against the form board.

4 You will want to spread a layer of gravel down inside the storm shelter form

area, evenly spread throughout the entire slab area before the rebar goes

down.

5 Inside the form use 1/2" rebar tied together with baling wire. Run the rebar the

length of the underground shelter slab area about one foot apart all the way

across and then cross those runs across the width of the slab area one foot

apart also. You should end up with a bunch of 1' X 1' squares with the rebar.

You want to turn the ends up about 3" from the side form boards where they

will be in the side walls.You can heat the rebar and bend a 90 degree angle

and turn straight up all the way around the slab. I would at least turn every

other one up inside the walls.

6 It is also a good idea to place some blocks of short 2X4's under the rebar in

several places to keep it off of the ground. You want your rebar to setup in the

middle of the concrete for strength and less chance of the underground shelter

slab cracking.

7 Once you have the rebar tied together and all the form boards braced up good

then it is time to call for the the concrete. To get your yardage amount of the

ready mix you will need for your storm building slab just multiply your length by

your width in feet, then multiply that by your thickness which would be 0.50 for 6

inches thick. If your thickness is 4 inches you would multiply the width and

length by 0.33, then you divide that total by 27.

8 So if your storm building slab was 8 feet wide by 10 feet long and 6 inches

thick, this would be your figures:8 X 10 = 80 X .50 = 40 divided by 27 = 1.48.

So you would need to order about a yard and a half of concrete. I would advise

getting the fibered concrete even though you have the rebar in place because

you want the storm shelter to have as much strength as you can get and this

will give you that.

Tips To Remember

Make sure you have your form braced up good with the outside stakes and kickers because the concrete will put a lot of pressure on them.

Bend your rebar ends to turn up out of the slab about 3 inches from the edge so they will be inside the storm shelter walls.

Wear gloves and eye protection when driving the bracing boards and nailing the kickers for the storm shelter slab.

Click on the link below to see part 2 of the storm shelter construction.

How To Build Your Own Concrete Storm Shelter-Part 2-The Walls