A lightweight integrated diagnostic approach for Macao Architectural Heritage using 3D laser scanning and NDT

This study tackles the challenges of documenting architectural heritage in Macao’s dense urban settings. Traditional methods are often inefficient and invasive for the complex materials of actively used temples. We propose a lightweight method that integrates portable 3D laser scanning with non-destructive testing (NDT), using the Kuan Tai and Tin Hau Temple in Taipa as a case study. A millimetre-accuracy 3D point cloud was used as a unified spatial framework to correlate multi-source inspection data. This framework spatially correlates multi-source data on elemental composition, thermal anomalies, and surface hardness. Our approach achieves high-precision digital documentation. It reveals that the primary degradation mechanism is sulfate-induced corrosion, caused by incense pollutants under high humidity. The entire system weighs under 4 kg, making it portable and minimally invasive. It provides a scientific basis for the preventive conservation and digital management of heritage in similar complex environments.