Eco-efficient lime/pumice mortars with sheep wool for heritage restoration: Life cycle and energy savings

Abstract

Currently, 40 % of CO₂ emissions and energy use are attributable to the building sector. Aside from thermal insulation levels and energy requirements, primary energy consumption, CO₂ reductions, and the environmentally friendly properties of the materials used are currently being considered when evaluating building sustainability and energy efficiency. Therefore, it is essential to optimize the use of ecological materials in buildings in order to make them as sustainable as feasible. Utilizing slaked lime and pumice powder as binders, nine distinct types of mortars reinforced with sheep wool fibers with comparable workability were examined. This research assessed the fresh, physico-mechanical, durability, life cycle assessment and thermal properties of restoration mortars reinforced with wool fibers and containing pumice powder in place of slaked lime at 0, 25, and 50 % replacement rates. The three percentages of wool fibers by volume that were used in this investigation were 0, 0.25 and 0.50 %. It was also investigated how well the combinations held up to high temperatures, dry shrinkage, and sorptivity. Microstructural analysis of the mixtures were made based on SEM. The findings indicated that the mixture with 50 % pumice powder and 0 %wool fibers showed the best compressive strength performance, exhibiting a strength gain of approximately 953 and 643 % in comparison to the control mixture at 28 and 90 days, respectively. The same mixture also demonstrated the lowest sorptivity and dry shrinkage, while the reference blend exhibited the lowest thermal conductivity. The mixture with 50 %PP and 0.50 %wool fibers showed the best high temperature performance.