This study proposes an analysis approach of the life-cycle of two types of social housing of « T4 single-storey houses ». This is to determine which phase of the life-cycle calls for special attention in the process of reducing the impact of this sector on the environment. In order to successfully carry out this task, we first carried out a general review of the LCA as a decision-making guidingn tool. Then, we alluded to social housing projects in Cameroon as the implementation framework of our guiding tool. Finally, after updating the database of some components of the buildig sector, e proceeded to the implementation on our two samples. Results obtained highlight the importance of the exploitation phase. More interestingly, considering all te twelve environmental impact indicators taken into account, the utilization phase that involves exploitation and maintenance is more predominant, causing 82 to 86% of the total impact, followed by the construction phase with 13 to 18%, and then by the demolition phase with 0.01 to 1%. As concerns the economic aspect, the utilization phase remains the most preoccupying. It represents at least 65% of the overall cost of the life cycle, also followed by the construction phase and then the demolition phase.