| 摘要 |
PROBLEM TO BE SOLVED: To provide a staircase unit capable of setting a direction of a bottom 7 of stairs from a lower floor to an upper floor in an arbitrary direction and improving transportation efficiency and equipment efficiency, a building unit and a method of constructing the staircase unit to the building unit.SOLUTION: The staircase unit is separated into an upper staircase unit 1A having a plurality of treads 3a-3k of the second and higher stages and a tread 2 of the first stage arranged at a diagonally downward part of the tread 3a of the second stage of the upper staircase unit 1A. The tread 2 of the first stage is quadrangular in the plan view, and a width of each side of the tread 2 of the first stage is the same as or greater than the width of the tread 3a of the second stage of the upper staircase unit 1A. |
