This paper investigates the energy efficiency in a segment of the building sector in emerging countries by analyzing and evaluating the energy efficiency of a social housing project in Brazil Energy efficiency measures and bioclimatic design strategies are developed in order to improve thermal comfort in this social housing project and to reduce the energy consumption and expenses of their residents The institutional barriers and constraints toward higher efficiency are described The results of this study show that there is a high potential to increase energy efficiency in social housing in emerging countries like Brazil The implementation and consideration of the energy efficiency measures and policy recommendations would contribute substantially to the goal to dampen the fast growth of energy demand in these countries. Moreover the improvement of energy efficiency in the social housing sector could be a driver for market transformation towards more sustainability in the whole building sector (C) 2010 Elsevier Ltd All rights reserved