Meisterprüfung Platten- Und Fliesenleger Practice Questions - Meisterprüfung Platten- Und Fliesenleger (Austria) Exam

Calcium sulfate screeds lose significant mechanical strength and become water-soluble when wet, and they react with cementitious adhesives to form expansive ettringite if not isolated by a barrier primer. Calcium sulfate screeds exhibit higher alkalinity (pH > 12) than cement screeds and undergo hydraulic curing that increases strength when continuously submerged in water. Calcium sulfate screeds exhibit significantly higher thermal expansion coefficients than cement screeds and do not require movement joints even on heated floor assemblies. Calcium sulfate screeds cure exclusively through carbonation from atmospheric carbon dioxide, making them completely impervious to water vapor and moisture damage.