First of all, you must decide the location of your concrete storm shelter. It will be better to build it at a location where you can easily move during harsh weather conditions. Generally, the backyard of a house is considered as the best place for building a concrete storm shelter. However, if you have any other place which you think is more appropriate, you can build it there.
After selecting the right place for building the storm shelter, you have to take all the required measurements. It is very important to take the measurements accurately because you will not be able to build a good storm shelter until or unless all the dimensions are right. You must check all the measurements at least twice so as to confirm the accuracy.
FEMA (Federal Emergency Management Agency) provides all the necessary details to construct the storm shelter. You should get the booklet from FEMA in order to design and construct the storm shelter in your house. There are many different ways with which you can build your storm shelter. You should choose the one which will fulfill all your requirements and prove out to be best for your place.
You can also download the photographical representation of various stages of the storm shelter from the official website of FEMA. The graphs and images provide great help in building the storm shelter.
Build the wall by placing steel rods at the marked spots. Make the frame and put the concrete in it to make the walls firm. Let the concrete dry out before proceeding any further.
In the end, put the steel door and tighten it with the help of the bolts. You should tighten the bolts with full strength so that the door stands firmly.