C.F. Møller Architects has developped two residantial concept designs for the Danish manufacturers of lightweight pre-fab concrete panels: A triangular single-family house, called Nordpilen ("north pointer") because of it's openness to the south and minimal north exposure, as well as a modular design for collective housing made up by four different apartment types linked by adaptable staircores, which allow the design to be optimized for solar orientation and site specifics. Both houses are designed according to the 'passive house' principle.