Prefabricated spiral staircase for square stairwell - provides complete floor plan cover with two step types giving corner and side configurations

摘要

The prefabricated spiral staircase for a square stairwell or to be placed in an angle between two perpendicular walls provides complete floor plan cover by using only two different shapes of steps. The steps are used alternatively two of the first type, followed by two of the second type. The first type are placed either side of the stair well diagonals, adjoining faces having exterior 45 degree angles forming together the 90 degree diagonal corner. Each step has a socket on its interior corner to slide over the central pole and abut on the socket and step beneath.