Methods for porosity measurement in lime-based mortars

Porosity is one of the most common determined physical properties of building materials mainly because of its influence on important properties such as strength and durability. Porosity especially in lime-based mortars occupies an important volume. The heterogeneity as well as ageing effect often found in these mortars that have been used for the construction of monuments and historic buildings, make porosity a difficult property to measure. In the paper the porosity of old lime-based mortars is estimated using four well-known techniques. The advantages and restrictions of each method are discussed. The porosity values differ according to the methodology followed. The type of information gained by each method could give valuable data for the material’s quality.