Abstract

Improving a building’s envelope is one of the more practical solutions to reduce its heating demand and environmental impact throughout its life cycle. However, it can significantly vary with geographical characteristics and socioeconomic conditions. Accordingly, this study aims to develop a Life Cycle Assessment (LCA) of social housing located in two cities (Puerto Montt and Punta Arenas) in southern Chile using different insulation materials (mineral wool and polyurethane board) and thicknesses (from 1 to 15 cm). The heating demand is determined with Energy Plus, and the environmental impact is evaluated though a LCA from the cradle-to-grave by considering a functional unit of 1 m2 of the total dwelling living area. According to the results, the heating demand could decrease by 54% using mineral wool and by 57% using polyurethane boards for the base case in Puerto Montt. A similar pattern is registered for Punta Arenas, decreasing by 55% using mineral wool and by 58% using polyurethane. The increment of thermal insulation thickness produces an energy saving of 57-60% concerning the base case, and a reduction of the total environmental impact between 18-29% for both cities. Significant environmental impacts were depicted for Puerto Montt (600-850 Pt/m2) in spite of a lower energy consumption compared to Punta Arenas. It is attributed to the use of firewood in heating and to the energy matrix. This finding demonstrated that life-cycle results are more sensitive to specific regional conditions than climate. This result could identify more sustainable solutions for social housing construction involving site-specific conditions.