This study evaluates the accuracy of preliminary calculations for load-bearing elements in office buildings in Sweden using Nodon software. By comparing the calculation results from the software with actual data from 3D models, the research identifies discrepancies. The analysis focuses on the environmental impact of structural elements during the A1-A3 stages. Results indicate differences in material quantities between 3D models and Nodon software, ranging from -14% to +25%, particularly for interior concrete walls. The study concludes that while Nodon’s estimates are within an acceptable range, there are possibilities for improvement to get more accurate quantities in the early stages. Dominance analysis reveals that hollow core slabs and steel beams are the primary contributors to global warming potential, with an approximate total of 70%, suggesting targeted strategies for emission reduction on those specific elements.