The staircase that is located outside the building usually is made of concrete. And usually these types of stair construction need a reinforcement with a steel net. There is a reinforcement staircase where the steel is actually defining the steps of the staircase and it need to be properly installed so as showed in the images bellow.  See the gallery images and learn how this net is installed making a firm staircase. This type of building staircase can be also used for interior use, but it is rare in comparrison with the outdoor staircase.

 

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