Twisted staircases can give more charm to the space. However, they are more complicated and you might feel a little bit intimidated by the construction and the planning. Furthermore, this might not be an easy do it yourself project, but you have to consult a professionals for this field. There are several types of spiral staircases and all of those have different characteristics that should be taken into consideration. One of the types (slabless staircase) is illustrated here.