2024-25_NTCA_Reference_Manual_dig_dwnld

Etched or Dull Areas in Polished Natural Stone Surfaces This section does not address stains associated with dull areas. See "Stains," (page 162).

Problem

Prevention

Cure

Use coasters under glasses and food.

Exposure of calcareous stone surfac es to mild acid, such as found in fruits, vinegar, juices, and other food products commonly found in kitchen and food ser vice settings. Exposure of calcareous stone surfaces to acidic cosmetic prod ucts or urine in bathroom settings.

Floor should be refinished by qualified persons.

Protect stone surfaces from cosmetic stains and spills. Clean all spills prompt ly. Protect polished stone surfaces with a topical sealer manufactured for that pur pose.

Concave areas and areas damaged by acid or urine may require grinding or re placement. Use honed or other non-reflective finish es, or use stone varieties with high abra sion resistance index and chemical resis tance.

Floor should be refinished by qualified persons.

Clean stone surface after installation with a neutral (pH7) cleaner. Rinse and wipe dry. Apply a sealer when necessary to help protect the surface. Follow grout manufacturer’s instruc tions. Remove grout residue from the stone surface as soon as possible fol lowing installation. Use a penetrating or impregnating sealer prior to grouting per manufacturer’s directions.

Cleaning with solutions containing ac ids, alkalines or solvents used for both initial cleanup and ongoing mainte nance.

Floor should be refinished by qualified persons.

Alkalinity of cement-based grouts.

Consult care and maintenance manufac turer for a recommended alkaline cleaner or specialty products.

Floor should be refinished by qualified persons.

NTCA Reference Manual | 2024 / 2025

165

Chapter 6 | Natural Stone Installations