In Situ, Non-Destructive Testing for Evaluating the Role of Pointing Mortar in Preventive Conservation Strategies. A Case-Study on Reigate Stone at the Wardrobe Tower, Tower of London

Research at the Tower of London's Wardrobe Tower reveals that hydraulic lime mortar (NHL3.5) less effectively regulates moisture in Reigate Stone masonry compared to lime putty mortar, yet older NHL mortars can perform similarly despite initial incompatibility. Non-destructive testing over two years showed that while pointing mortar type influences stone moisture regulation, its impact is secondary to the stone's inherent properties and micro-contextual factors like exposure and topography. The study underscores the need for tailored conservation strategies addressing specific decay mechanisms, including additional protective measures against moisture ingress, to ensure sustainable preservation of vulnerable historic masonry.

Michette, M., Viles, H., Vlachou, C., & Angus, I. (2021). In Situ, Non-Destructive Testing for Evaluating the Role of Pointing Mortar in Preventive Conservation Strategies. A Case-Study on Reigate Stone at the Wardrobe Tower, Tower of London. Minerals, 11(4), 345. https://doi.org/10.3390/min11040345