The main focus of this project is to maintain energy-efficient components and assets in existing buildings. Artificial Intelligence (AI) will be applied first to predict the building's components' future energy consumption and health conditions. Then, by having these data, a novel maintenance management and energy management optimization model will be created to perform the correct maintenance tasks and activities at the right time to reduce the maintenance costs and energy consumption. Therefore, by having a proper maintenance schedule for assets in existing buildings, this project aims to improve energy efficiency and increase energy cost savings.