Rezumat/Abstract. Air lime mortars constitute an essential traditional material for built heritage restoration, but they show a significant vulnerability to capillary water absorption, the main cause of degradation by salt crystallization and wetting-drying cycles. This study examines the impact of incorporating calcium stearate-based water repellents into lime mortars formulated with a 40% substitution of the binder by Natural Pozzolan from Souahlia or crushed Sanitary Ceramic Waste. Six formulations were developed with different dosages of calcium stearates and characterized up to 700 days of curing. The characterization specifically analyzes compressive strength, the capillary water absorption, and the evolution of carbonation assessed by the phenolphthalein indicator, over a curing period of up to 700 days. An innovative methodology for quantifying carbonation by image processing was developed to overcome the issue of Liesegang rings at late stages. The results demonstrate that the WR significantly reduces the capillary sorptivity coefficient (up to 20%), without compromising mechanical properties or the complete carbonation progression confirmed at 700 days for all mixes. Mortars based on ceramic waste show superior and durable hydrophobic effectiveness. This research provides lime mortars that are both hydrophobized and fully carbonating, capable of limiting moisture-related decay while remaining compatible with historic masonry, thus directly improving the durability and reliability of conservation interventions. By valorizing local Algerian pozzolan and ceramic waste as high-performance additions, it supports a more sustainable, context-adapted approach to heritage restoration that reduces resource extraction and industrial waste.

Cuvinte cheie/Key words: carbonation, durability, sorptivity, pozzolanic additive, liesegang rings

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