With the aim of moving towards a more sustainable society, hospital buildings are challenged to decrease their environmental impact while continuing to offer affordable and qualitative medical care. The aim of this paper was to gain insight into the main drivers of the environmental impacts and costs of healthcare facilities, and to identify methodological obstacles for a quantitative assessment. More specifically, the objective was to assess the environmental and financial impacts of the general hospital Sint Maarten in Mechelen (Belgium) by using a life cycle approach. The hospital building was analyzed based on a combination of a simplified life cycle assessment and life cycle costing. The “MMG+_KULeuven” assessment tool was used for the calculation of environmental impacts and financial costs. The study revealed that the environmental impact was mainly caused by electricity use for appliances and lighting, cleaning processes, material production, and spatial heating, while building construction and electricity use caused the highest financial costs. The most relevant impact categories identified were global warming, eutrophication, acidification, human toxicity (cancer and non-cancer effects), and particulate matter. Various methodological challenges were identified, such as the adaptation of existing methods to ensure applicability to hospital buildings and the extraction of data from a Revit model.