Inventory regionalization of background data: Influence on building life cycle assessment and carbon reduction strategies

Robust carbon reduction strategies are needed to meet climate targets, especially for emissions from building materials. Although research has shown that the production of materials can be influenced by local conditions, such as the energy mix, the impact of regionalization on embodied emissions from buildings has not yet been fully explored. In this paper, we investigate the impact of inventory regionalization on the life cycle assessment of buildings and its influence on greenhouse gas (GHG) reduction strategies. This is performed by first developing a consistent, automated and reproducible method for regionalizing the production process of building materials for all countries. We then apply life cycle assessment to a building for all European countries using the created regionalized processes. The results show strong deviations for certain countries, reaching a difference of up to 17% to the regional average data. When investigating the influence of regionalization on the choice of typical GHG reduction strategies, results show that the choice of strategy can be influenced by the regional context, supporting the need for greater geographic representativeness of building materials inventories for successful GHG emissions reduction pathways. Regionalization can also support the development of more accurate product-specific environmental product declarations (EPDs), which currently rely on average background data.