Probabilistic Life Cycle Cost Model for Sustainable Housing Retrofit Decision-Making

Sustainable housing retrofitting is an effort to convert a house to a low energy facility, to analyze the deconstruction techniques, and to evaluate the alternatives for installing reused/recycled materials. In order to make the decision of both designing and pursuing a green housing refurbishment approach, there is a need to perform a life cycle cost assessment to evaluate how each alternative influences the cost of construction, long-term costs (e.g., maintenance, utilities) and environmental impacts. This study presents a Monte Carlo simulation for estimating life cycle costs (LCC) of a case study house built in the 1960’s. The study identifies the significance of proposed retrofit activities on the house’s LCC. The results show that the cost of building may increase if we select a sustainable retrofit approach, but that the long-term costs would decrease. This paper also concludes that an optimum selection of retrofitting activities could minimize the life cycle cost of a project.