Quattro

The brief asked for a multi-storey, mixed-use residential building in a densely built new development area. The answer was a highly technical passive house made from the simplest and most CO₂-efficient materials available: wood and earth.

The seven storeys house 29 residents. A bicycle shop and a bar occupy the ground floor; the three residential floors above hold two- and three-room apartments for singles, couples and families; from the fourth floor upwards there are studio apartments for students, together with communal rooms. Throughout the building a ceiling height of 3.2 metres allows sleeping areas to be layered vertically, which opens the small units up and adds usable floor area.

The structure is built entirely in timber and clad in a prefabricated rammed earth facade with full thermal performance. The combination keeps the flexibility of timber construction while gaining what earth does well: moisture regulation, thermal mass, a healthy indoor climate. All timber cross-sections were dimensioned to meet German fire protection standards.