In today’s world, sustainability has become a crucial concern, and the building sector is no exception. One major issue in this regard is the lack of a comprehensive rating system that can evaluate the heritage elements of buildings and help facility managers make informed decisions about their rehabilitation. To address this gap, the present research aims to develop a comprehensive rating system for heritage buildings that not only assesses various building components but also optimizes expenditures by efficiently allocating limited budgets. The system will be applied to a real case study, the Murabba Palace in Riyadh, Saudi Arabia, to demonstrate its effectiveness. The system has the potential to assist facility managers and governments in preserving heritage buildings and enabling future generations to learn about their history.