AbstractIntroduction – The construction industry accounts for a significant share of society´s resource use and climate impact and therefore holds a major responsibility in promoting ecological sustainability. A key challenge is that sustainability aspects are often not integrated into the early stages of decision making, where critical material choices are made. The aim of this study is to develop a draft checklist to support property owners and other stakeholders in these early stages, focusing on material choices with low carbon emissions.Method – The study has qualitative approach and is based on interviews and document analysis. It focuses on understanding complex decision-making processes in social contexts rather than testing hypotheses. The method is suitable for studying complex and difficult-to-overview phenomena where the researcher has a close connection to what is being examined. The empirical data consists of interviews with actors in the construction industry and documents from previous research on the climate impact of building materials.Results – The results show that material choices in the construction industry are primarily driven by tradition, experience, and economic factors rather than systematic sustainability assessments. Smaller companies often lack structured decision-making tools, while larger organizations partially utilize climate budgets and certifications. Despite this, detailed tools for assessing the climate impact of materials are often lacking. The study indicates that the use of Environmental Product Declarations (EPD:s) and checklists can facilitate the selection of materials with lower carbon emissions and reduce climate impact during the production phase.Analysis – The analysis shows that material choices and decision-making bases in the construction industry vary between organizations. Smaller companies often base decisions on experience and tradition, while larger actors more frequently use sustainability-related tools such as environmental certifications and climate budgets. However, structured internal methods are often lacking, making external requirements and individual expertise important. Financial constraints and established working practices make it more difficult to use more climate-friendly materials.Discussion – The discussion shows that material choices in the construction industry are primarily driven by tradition, experience, and economic factors, which limits the use of sustainability based, decision making tools. Despite the availability of EPDs and climate budgets, these are not used systematically. At the same time, there is a clear demand for checklists to support more sustainable choices. The study indicates that structured tools can reduce uncertainty and facilitate the integration of ecological sustainability in the early stages of the decision-making process.Keywords – Decision making basis – construction materials – Ecological sustainability – EPD (Environmental Product Declaration) – Sustainable construction – Material selection