Noting spalling from deteriorated buildings post a great, but hidden safety hazard to the public, this project aims to introduce an “AI Drone Building External Wall Spalling/Water Seepage Detection System for Deteriorated Buildings” that leverages AI technologies to address the challenges in improving effectiveness and efficiency of public services while enhancing public safety in the area of potential concrete falling incidents. In addition, the developed system can help safeguard the public officers’ occupational safety and health. By integrating advanced sensors, AI technologies with drone surveillance, we can automatically detect and actively prevent hazardous incidents caused by spalling. The outcome of the proof of concept project will facilitate wider adoption on urban built hazard detection, building law enforcement and maintenance surveillance by the Hong Kong Government.