From the architect. The main concept is "A Spiral Porch in tokyo" -challenging to open (or close) the privacy to urban environment. The "Porch" was essential to traditional Japanese house, therefore it is one of the most nostalgic space for all. Recently in Tokyo(JPN), lands for build some architecture are very expensive. And therefore that made us give up to create the "porch".
So we decided to create the brand-new Engawa. Very narrow site forced to form 3-dimensional (spiral shaped) engawa structure. But this was a nice idea to create engawa outside of this ribbon. The ribbon makes shade and shadow in inside and outside. And each floor slabs, spirals, end roof are entirely made from steel plate T=4.5mm. So this house is very light weight to be supple for earthquake. No thick columns needed, all parts configure supple and strong mono-coque body.