Life Cycle Assessment (LCA) is an effective method for evaluating the environmental implications of building construction. However, it is mostly used for post-design reviews and rarely utilized to support or optimize design decisions during early design stages due to its complexity and professional expertise requirements. This study aims to assess and reduce the environmental impact of a 20-story apartment building through appropriate design and material selection. Multi-story buildings are commonly preferred in larger towns and cities, but their development can have significant environmental impacts on the surrounding region. The "cradle-to-grave" LCA approach is used to determine the adverse hazards associated with the 20-story building model, including carbon dioxide (CO2), sulphur dioxide (SO2), phosphate ((PO4)3), trichlorofluoromethane (CFC-11), and energy consumption. Environmental effect categories, such as the potential for global warming, ozone depletion, acid rain, and others, are described using these corresponding amounts. LCA analysis is conducted using computer software. This research work estimates the environmental impact of multi-story building construction using the LCA tool, which can help identify upcoming challenges in constructing environmentally friendly buildings without affecting society for builders, entrepreneurs, and financiers.