Energy consumption in buildings accounts for a significant percentage of total world energy utilization. Great efforts have been made in order to reduce fossil energy consumption and mitigate its depletion by means of energy efficiency directives. The national transposition of such directives generates regional regulations that might be counterproductive if it is not clear which one is more restrictive. The main goal of this paper is to evaluate the potential of energetic savings of the dwellings in Catalonia and its economic impact, according to different scenarios of efficiency that have been defined according to current regulations at state and autonomic level. To achieve this objective, thirteen typologies of dwellings have been defined in order to categorize the stock of buildings in Catalonia. Simulations with LIDER software have been carried out in order to obtain the heating and cooling demand for each typology of dwelling in different climatic zones and orientations. The economic impact of each scenario has been stated as well. We show that the best normative scenario is not the regional but the national one, and only when full limitations imposed by the state regulations are fulfilled. Following the latter 6.4% reduction in CO2 emissions would be achieved, whereas following the former gives us only 2.8% reduction for year 2015. These results have been obtained considering a base case scenario without any energetic measures implemented for the same time line Peer Reviewed