This study presents a method of monitoring historic concrete and associated repairs. A case study of Boathouse 4, Portsmouth Historic Dockyard, UK is presented. Boathouse 4 is an iconic building within Portsmouth Historic Dockyard which was constructed during the 1930’s rearmament period. It was used during World War ll to construct the three-man midget X-Craft submarine. The building was restored and converted into a Boatbuilding Skills Training Centre in 2015. A field investigation was conducted to analyse the concrete damage and to monitor microscale changes to the surface of the original concrete and repairs over a period of three years. Three patches of concrete lying in the undercroft of the building, located in an intertidal zone were chosen to be monitored for material changes as part of an ongoing PhD research study. These areas were scanned three times at intervals of up to 9 months within three years using a NextEngine portable laser scanner to obtain high-resolution 3D images of the concrete surface so that gradual changes to the microtopography, appearance and texture of the concrete surface and associated repairs could be detected. The data was analysed and the results indicated slight topographic changes in the concrete surface as well as the colour of the cementitious repair materials