I was invited by the architect Ramon Aguirre Morales, to join him in the Nochixtlan (Mixteca, Oaxaca) workshop. It consisted of redesigning an existing adobes building, which originally was covered with galvanized iron sheets. The new building will be used as a library. We though to preserve the existing 1980’s building and improving it with a better roof: an earth one. We designed a wooden beams, which allow light and fresh air to get into easily. The girder system made the assemblage very quick, in roughly two days we set up 13 beams, and covered it with a bamboo (carrizo) secondary structure (first stage), just ready to be covered with a earth layer (second stage).