Tokyo firm Office of Ryue Nishizawa has created an undulating concrete roof to span a long weekend house on a promontory towards the Pacific Ocean in Chile. House in Los Vilos is a retreat on the Chilean coast that was completed by the eponymous Japanese studio of Pritzker Prize-winning architect Ryue Nishizawa, who also runs firm SANAA with architect Kazuyo Sejima. Office of Ryue Nishizawa designed the wavy roof to follow the contours of its site – a rocky high land that juts out to…