Traditional mortars in North-East Yorkshire: Part 2 — Analytical results, technical evaluation and implications for practice

This second part of the two-part paper which began in Journal of Building Survey, Appraisal & Valuation Volume 15, Issue 1 presents the scientific, technical and interpretative findings of a major mortar analysis project undertaken in Bransdale in 2024. Laboratory investigations, including compositional, mineralogical and microstructural analysis, reveal a consistent pattern of non-hydraulic and feebly hydraulic lime mortars, characterised by high lime content, fine limestone or quartz aggregate, and evidence of traditional hot-mixing methods. The results clarify the performance characteristics of historic mortars within a challenging climatic environment and provide insights into slaking behaviour, carbonate development, aggregate selection and the role of accessory materials such as coal, ash and clay. The paper evaluates the implications of these findings for current conservation practice, demonstrating the functional advantages of lime-rich, capillary-active mortars for moisture management and fabric durability. Additional case studies and appendices document variations across sites and support the development of compatible repair mortars. The paper concludes by outlining future directions for research, training and kiln reconstruction, underscoring the value of evidence-based, regionally informed approaches to mortar conservation. The analysis for this paper was carried out by Bill Revie, whose technical input has been fundamental to the work presented here. This article is also included in The Business & Management Collection which can be accessed at https://hstalks.com/business/.