kazunori fujimoto architects completes house in ashiya, japan, with concrete spiral staircase

at the foot of mount rokko, japan, kazunori fujimoto architects has built a concrete residence comprising two squares, whose two levels are connected via a unique spiral staircase. house in ashiya is built as a geometrical composition, where its two square volumes make a constriction in a one-room space, and the dimensions of each architectural element have been carefully considered to maintain a spatial purity.

all images courtesy of kazunori fujimoto architects

surrounded by the green landscape of the mountain, kazunori fujimoto architects‘ house in ashiya is characterized by two concrete square volumes and an ambiguous relationship between inside and outside spaces. a curved, sculptural staircase, whose center is a straight line, connects the two levels of the residence while taking up a very small amount of space and allowing for the area under it to be used as a corridor. giving softness to the otherwise rigid interior, the curved sculptural staircase goes beyond its function and becomes the yorishiro (an object capable of attracting spirits in shinto religion terminology), which symbolizes the unity of the family in the house.

the residence is divided in two different levels, with the first square volume characterized by an open space in both floors, while the second one divided in smaller areas in the first floor, and in four rooms in the second floor using a cross-wall. the unique spiral staircase, which serves as a partition between the entrance and the bedroom, serves the use of minimal area in the plan for the stairs and corridor, and incorporates a minimum-thickness slab that allows the space under it to be used as a passage.

project info:

name: house in ashiya

architect: kazunori fujimoto architects

location: ashiya, japan