Cleaning is carried out by abrasive materials.

Uneven up to 10mm requires a primer in two or three layers, alternating layers of primer with layers of putty or plaster. Some primers for the ceiling require cleaning clean, cleansing from stains, mud before applying clean. Cleaning is carried out by abrasive materials. The quality of soils for the ceiling is determined by penetration into the thickness of the material. The deeper it penetrates the material, the better the primer.