The presence of moisture inside building materials decreases their thermal and mechanical performances. Knowing the variability of these properties as a function of saturation is essential both to evaluate the aging of the material over time, and to characterize the durability of the new materials introduced in the restoration. The study presents an experimental research, carried out on some bricks produced for the restoration of historical buildings in Madrid, aimed at evaluating the percentage change of thermal and mechanical strength of these materials due to the presence of water in different saturation levels.