A Swiss Chilean family wanted to build a home in their home, in order to share with other foreigners in a small community. The existing house already occupied the maximum portion of the land allowed by the local regulations, so the growth strategy had to be developed in a vertical way. The triangular geometry of the site and the minimum distance to the neighbors´sites allowed by the norm posed some difficult questions regarding the available space for the housing extension and the number of openings with which views, sun and natural light could be achieved. An adequate balance between these variables became the purpose of the project. The proposal follows the theoretical line of the minimum distance in all its contour, interrupted only by the openings to the north destined to capture the solar path in winter. A mobile wooden lattice completes the perimeter of the volume to block the sun in summer and ensure privacy between neighbors. The meeting and resting spaces occupy the north orientation and a patio opens to the south to guarantee the natural ventilation of all the enclosures. In addition, this patio ensures the natural illumination of the circulations. The service spaces, bathrooms and cellar are illuminated and ventilated by skylights. The solar capture and super insulated walls favor the feeling of comfort in winter. A super insulated roof receives a layer of pebble gravel to delay the entry of heat in summer. The gray waters are separated in order to have in the future, an accumulation tank that allows reusing water for irrigation.