<b>ABSTRACT</b></br>

A commercial masonry rendering mortar is tested in this study of the classical correlation between structure and mechanical properties. Porosity, capillary absorption of water and mortar shrinkage are all analyzed. Special emphasis is placed on the development of mortar strength, stiffness, and damping characteristics including sound muffling. All these properties are related to the microstructure of the mortar in the hardened state and to its moisture content. The numerical results showed different values for the Young’s moduli of the rendering mortar under both tension and compression, and an outstanding capacity to dissipate vibrational energy. Freeze-thaw and wetting-drying durability tests were also performed on the mortar with good results.</br>

<b>ACKNOWLEDGEMENTS</b></br>

The authors wish to express their gratitude to: the Junta de Castilla y León (Regional Government) for funding UIC-231 through project BU119P17 also assisted with FEDER Funds; the Spanish Ministry through contract RTI2018-097079-B-C31 (MCIU/AEI/FEDER, UE), and finally, our thanks to the Basque Government research group (IT1314-19). Our thanks likewise to ONEXIT mortars for supplying the materials used in this research.