During my learning process, drawing was used as a tool. The first approach to construction was made by the study the Oporto’s traditional house. Several visits to one of the old city houses resulted in many drawings that helped to understand and, in this particular work, to draw the possible configuration of a roof structure. The constructive system of Oporto’s traditional housing became a reference for further constructive drawing. It works now as a conceptual tool for new inventions in that field.