Water uptake kinetic and balance moisture of some commercial building materials: clay bricks, Keraterm blocks, sand-lime bricks, aerated concrete, expanded clay concrete and concrete are compared. The same properties of semi-dry pressed sample fired at temperature 10000C of different Latvian clays are compared. Influence of porosity industrial products and materials obtained in laboratory on above mentioned properties as well as suitableness of these materials by living-house building are evaluated. Advantage has materials with low moisture balance. Thermal insulating properties of such materials depends not only on the porosity and pore size distribution, but also on the nature of crystalline phases formed in firing process.