ABSTRACT
Water transport occurs in brick, stone and concrete because of their porosity. Porous materials are almost invariably permeable and both liquid water and water vapour can penetrate into the pores and per- meate through them. We discuss the porosity in relation to the min- eralogical constitution and manufacture of these materials. Topics include: how the porosity is described and defined; and how it is measured. We review values of the porosity for a wide range of ma- terials; how the porosity is affected by temperature and stress; its scale dependence; and the distribution of pore size.
