Nowadays, one of the current concerns of the United Nations and the European Union is to offer more reliable mechanisms aimed at reducing energy consumption and carbon emissions on a building scale. The new required recommendations can be applied to all countries of the world. The main objective of this study is to evaluate, analyse and compare the indoor air condition (comfort rate and CO2 concentration), and energy consumption, prevailing in a family building built in eight cities (Douala, Kinshasa, Abidjan, Lagos, Pretoria, Dakar, Antananarivo and Addis Ababa), located in eight countries (Cameroon, DRC, Cote d'Ivoire, Nigeria, South Africa, Senegal, Madagascar and Ethiopia) in Sub-Saharan Africa. In addition, this study assesses the total cost of the life cycle of a new building over a period of 50 years in each country. Parameter simulations and optimizations are carried out over three periods (current, 2030 and 2050) with Design Builder software renowned in this area. The results showed that the comfort potential is around 10-21% higher in the residential buildings located at altitude compare to those ones in coastal regions. The thermal comfort range is found between 20 degrees C and 29 degrees C in these different cities. The preferred thermal environment in altitude regions, where it makes cold, should be 'slightly warm', corresponding to around 1 ?C above the neutral temperature, in order to satisfy the majority of the building occupant. In addition, the preferred thermal environment in coastal regions, where it makes warm, should be 'slightly cold' , corresponding to around 1 degrees C below the neutral temperature, in order to satisfy the majority of the occupants of the building. Finally, the building's Life cycle cost (LCC) ranges between 25% and 35% for construction cost; from 30%to 40%, for operation cost; between 2% and 3% for maintenance cost; between 9% and 15% for energy cost on the whole LCC in Sub-Saharan-Africa.