Ecological transition for the built environment: Natural insulating materials in green building rating systems

The regenerative concept of design and construction is gaining relevance, as it is changing the sustainability paradigm toward the ecological transition for the built environment, representing a track on which economic and financial support policies are currently being routed. One of the ways to achieve ecological transition is to use sustainable insulating materials in buildings. In addition, certification systems were developed to actualize and renovate the concept of sustainability. The literature review showed that there no studies dealing with the influence of different insulating materials on green building rating systems. This research apply ITACA and LEED protocols to quantify the impact of insulating materials on certification levels. Starting from the comparison between these protocols and the analysis of credits related to sustainable building materials within LEED, the rating systems were applied to an existing multystorey residential building by varying the insulating materials for the building envelope, such as glass wool, expanded polystyrene (EPS), and two types of natural materials, e.g. mineralized wood fiber and kenaf. The results showed that every envelope configuration obtained the certification in both protocols, except EPS which did not obtain the certification in LEED. However, although kenaf and mineralized wood fiber can be considered sustainable materials, they do not reach the maximum achievable category score influenced by the insulating material choice.