The Rudiments of Traditional Mortar Preparation and Use

This paper seeks to summarise recent major shifts in the understanding of the nature and provenance of traditional mortars, the nature of the lime most used for the preparation of these mortars, as well as the methodology of the crafts in their preparation.It draws upon the author's experience of designing and using such mortars over a 20-year period, but also upon extensive research into old texts about lime and mortars written over the last 2,000 years, as well as upon extensive analysis of primary building accounts from England and elsewhere.It also references an expanding body of academic research in the characterisation of composition, as well as of the performance of such mortars, itself a significant shift in focus and understanding.It will set out the primacy of the quicklime slaking method in the delivery of successful mortar performance, optimal in the context of traditional building technology, and will reiterate the absolute importance of observing traditional lime choices, slaking method, rules and mortar proportion in the achievement of durable mortars of optimal performance for the like-for-like and compatible repair of traditional buildings of all kinds and status.