Thermal performance of sawdust and lime-mud concrete masonry units

Abstract Over the past three decades, growing interest in the properties of thermal envelopes and their enhancement has led to the development of new sustainable materials. Nevertheless, Concrete Masonry Units (CMUs) with negligible thermal properties are still widely manufactured in unsustainable processes for use in the thermal envelopes of buildings. Hence, this research aims to reuse certain by-products for the development of CMUs with better thermal properties. In addition to the reference concrete, one set of blocks was manufactured with 5% sawdust in substitution of fine aggregate and another set of blocks with the same level of fine aggregate replacement together with 15% lime mud in substitution of cement. The physical, mechanical, and thermal performance of the CMUs evaluated in this paper showed that the addition of sawdust in the CMUs improved their thermal properties. On the other hand, the addition of lime mud partially counteracted the decrease in strength caused by the incorporation of the sawdust.