Integrating environmental and thermal performance: A digital decision-support tool for Brazilian building design

The impacts of climate change have intensified the search for strategies. The building sector deserves attention due to its contribution to greenhouse gas emissions. Efforts have focused on operational energy; however, embodied impacts are relevant. In this context, the selection of construction materials and systems must address thermal performance requirements and environmental impacts. Integrating these aspects remains challenging, especially in developing countries, where training gaps, limited budgets, and the complexity of Life Cycle Assessment (LCA) tools restrict application in design practice. This study proposes a digital decision-support tool that integrates thermal and environmental performance for wall systems considering life cycle stages A1-A3 (cradle-to-gate), enabling early-stage design decision-making. The research follows five stages: (i) selection of representative systems for tool integration; (ii) definition of thermal performance assessment based on Brazilian and international standards; (iii) definition of environmental performance assessment using LCA; (iv) digital tool development (interface design and system architecture); (v) discussion. A total of 42 wall systems in Brazil were evaluated. The results reveal trade-offs between thermal and environmental performance. In steel frame systems, transmittance drops from 2.66 to 0.45 W/(m 2 .K) with insulation, while increases of 26–86% are observed in GWP-total, ADPF, ODP, and POCP, depending on insulation thickness. Differences among construction typologies highlight the influence of material composition on environmental indicators. The tool enables visualization and comparison of relationships, helping designers select wall systems that balance thermal and environmental performance. By bridging the gap between LCA and design application, the tool facilitates early-stage, low-impact decision-making in building design.