Lime

Calcium-based binder produced by burning limestone in traditional kilns and slaking the resulting quicklime with water. In the southern Moroccan earthen tradition lime is used principally as a stabiliser added in small proportion to the upper courses of pisé walls — improving abrasion resistance at the wall head and around openings — and as a binder in tadelakt and lime renders. Pure lime construction is rare in the pre-Saharan corpus; the dominant role of lime is as an additive to earthen mixes and as a finishing render. The traditional supply chain (artisanal kilns, local quarries) has largely collapsed and contemporary restoration projects typically import industrial hydraulic or hydrated lime, raising questions of compatibility with the original earthen substrate.