As it has been observed along the years, the unsustainability of the built environment is due to the high resources consumption and low indoor air quality of the existing building stock. In order to support the sustainable refurbishment design of buildings, and to meet European goal to achieve nearly zero-energy consumption standards in buildings in 2020, it is urgent to define guidelines that can be implemented since the earlier stages of the design. This paper defines guidelines to optimize the sustainability of a residential building and presents the process of sustainable building refurbishment, applied to a case study. To achieve this goal, the definition and evaluation of a group of procedures to be implemented, and a cost-benefit analysis applied to a case study was performed.