Temperature and distortion of an existing wall sample were measured to determine how solar heat affects tile finishing and the base aside with heating-cooling repeat test on lab specimen to examine how adhesive strength falls.
In outdoors, wall temperature rose by solar heat caused distortion between tiles and concrete, which expand in different degree. In year-round fluctuation, contraction under declining temperature caused relatively similar gap. In this test method, major cause of decrease in adhesive strength turned out to be the distortion gap caused by water absorption expansion of the concrete.