The basic concept is of a house within a house, similar to a Russian doll. The approach generates three types of spaces, the interior, the exterior and an intermediary space. The intermediary space can be used as a garden or terrace and acts in a similar way to a greenhouse or double-glazing. It allows the occupants to lengthen the time for outdoor living in spite of the harsh climate. All windows in the internal space open on to the intermediary space, which in turn has windows to the exterior. The typical section is a self-supporting steel structure. The same section acts as a thermal conductor, absorbing the heat from the mass of the house and redistributing it to maintain comfortable temperatures in winter and transferring the heat in the summertime to the outside. The house is open toward the south to take advantage of passive solar gains, while the north buffers the cold with a closed insulated steel tile surface. The outer structure is open to definition by the owner, who is able to choose the use of colours and patterns to personalize the home. The steel sections can be added or subtracted to create additional home variations.