This paper delves into the mechanisms of action between the physical properties and the frost resistance of structural clay products. By reason of their outdoor application range, such structural clay products as split tiles, clinker bricks, ceramic tiles, building bricks and roof tiles have to meet special frost-resistance requirements. Nevertheless, even standards-compliant products with good properties often suffer frost damage, despite having been installed correctly. Indeed, the presently applicable test standards do not fully enable the frost-resistance qualification of structural clay...