The house intended for a large family was designed in order to overlook the landscape in Covilhã, a small city in Portugal, southern Europe. Embraced by this house, a courtyard protects us from the hot climate. Sustainability was an objective since the beginning of the project. This eco house includes all state of the art techniques to increase sustainability and energy, eficiency and low carbon emissions on construction. Thus, the use of a light steel frame construction, the rainwater reuse, passive solar energy and the development of an excellent thermal insulation, everything has been considered in order to achieve the best energy autonomy and efficiency.