Abstract:While there exists an international trend to develop zero or near zero emissions building solutions by 2020, and European governments continuously update their building regulations to optimize the building envelope and energy systems to achieve this during the building use stage, at least in Spain the building regulations do not take into account the impact of emissions resulting from urbanization and construction activities prior to building use. This research studies in detail the entire emissions balance (and how it may be related to energy efficiency) in a newly built residential cluster project in Mancha Real (Jaén, Spain), and influences due to the choice of different urban typologies. For comparison, terraced housing and low-density, four-floor, multi-family housing alternatives have been studied. The present work assessed the life cycle of the building with the help of commercial software (CYPE), and the energy efficiency and emissions according to the legal regulations in Spain with the official software LIDER and CALENER VYP. After a careful choice of building and systems alternatives and their comparison, the study concludes that the major emissions impact and energy costs of urbanization and building activity occurs during construction, while later savings due to reductions in building use emissions are very modest in comparison. Therefore, deeper analysis is suggested to improve the efficiency of the construction process for a significantly reduced emission footprint on the urban environment.