This study proposes a methodological approach for the parametric estimation of construction costs in the residential sector, with particular reference to the Italian regulatory and economic context. Through the analysis of five case studies, the developed methodology allows for the organic structuring of cost items by means of a classification in working clusters and intervention categories, integrating the different typologies of surfaces in the calculation of the unit construction cost by taking into account appropriate homogenization coefficients with respect to the gross usable surface. The model is configured as a strategic tool for investors and public administrations, able to support economic planning and resource optimization in decision-making processes.