Klimatanalys i tidigt skede: hurtidiga val påverkar byggnaders klimatpåverkan.

Sammanfattning

This thesis investigates how LCA-based climate calculations can be applied in the earlystages of building design using BIM-based quantities and material data. The study wasconducted as a case study of a multistorey residential building, where a BIM model wasimported into One Click LCA to assess the building’s climate impact within life cyclemodules A1-A5. The aim was to identify which materials and building componentscontribute most to the climate impact and to evaluate how alternative material choices affectthe results. The results show that concrete is the dominant material group within the systemboundaries of the study. The reference model had a total climate impact of 566,677 kg CO₂ewithin A1-A5. Scenario analyses were carried out to examine the effects of generic concretedata, alternative concrete suppliers, and reused steel. Scenario 4, in which both alternativeconcrete and reused steel were applied, resulted in the largest reduction, decreasing the totalclimate impact to 384,679 kg CO₂e. This corresponds to a reduction of 32.1%. The studyshows that material choices, EPDs, and data quality have a significant influence on thereliability of climate calculations. The results also indicate that LCA combined with BIM canserve as a useful decision support tool in early design stages, provided that uncertainties inthe input data are handled transparently.