Despite its scarcely development in terms of construction, design and prefabrication, as well as the false prejudice of being considered a low quality product, timber, as a building material, is currently undergoing through a profitable moment in terms of industrial production in Chile. This research exposes and proposes new possibilities for timber architecture, contributing to create energy efficient houses. A house prototype was constructed in Traiguén city (38°25'S;72°68'W) for applying the constructive systems developed within the framework of a research project funded by CONICYT-Chile. Besides complying with an adequate architecture in terms of program and design, climatic factors and energy efficient criteria were thoroughly addressed. Climate of the city is Mediterranean, with high temperatures during summer and low temperatures during winter. The project considers the following constructive criteria: use of concrete framework, along with a good acoustic and thermal behavior for the floors, 2x4 timber walls with thermal insulation for winter and a ventilated chamber to lower temperatures in summer. An insulated timber truss for the roof with a ventilated chamber to avoid overheating during summer. A timber flexible structure makes future expansions easy and possible. A continuous envelope was designed to avoid non insulated areas, generating interspaces like a loggia and a vestibule heading south and a greenhouse to the north, protecting the inside of intensive rain and wind. Programmatic and efficiency criteria were met by orientating regularly used spaces, such as bedrooms, living room and dining room to the north. Service spaces such as loggia, vestibule, entrance hall, bathroom and kitchen, were oriented to the south, with smaller windows. Simulation and measurements have showed high thermal performance of the house during different periods of the year.