Maintenance and Cleaning of Ceramic Tile Surfaces
What the exam tests
This domain covers maintenance and cleaning of ceramic tile surfaces, including glazed ceramic, porcelain, quarry tile and related tile assemblies. The exam tests glaze and body identification, pH selection, agitation limits, grout protection, and safe removal of soap scum, grease and mineral deposits.
Core rules
- Identify the tile body and surface. Glazed ceramic has a glassy finish; porcelain is dense and low-absorption; unglazed or through-body tile may be more porous and stain-sensitive.
- Use neutral-pH cleaners for routine soil. Use alkaline cleaners for grease and oily soil. Use acidic cleaners for mineral scale only when the glaze and grout are compatible.
- Test in an inconspicuous area. Strong acids, including hydrofluoric acid, are unacceptable; acids can damage glazed surfaces, metallic glazes, glass tile and cementitious grout.
- Avoid abrasive powders and aggressive pads that dull glaze. High pressure can damage grout, edges and substrate.
- Treat grout as a separate surface. Do not flood grout lines; use soft brushes, controlled dwell, rinse and extract.
- Dry the surface and address standing water; seal grout only after it is clean and dry, and do not seal glazed tile.
Worked example
A porcelain bathroom floor has white hard-water scale and soap scum, with cementitious grout lines. Acid descaler may dissolve scale on the porcelain, but it can attack the grout. The safer process is to pre-treat with a compatible cleaner, keep acid off grout, use short dwell, agitate the tile with a soft pad, rinse thoroughly, extract and dry. The reasoning: porcelain is acid-resistant, but grout is not; cleaning must protect the assembly, not just the tile face.
Traps
Using acid on acid-sensitive glazes or grout; sealing glazed tile; using abrasive pads on polished glaze; over-wetting substrate; assuming all ceramic tile is porcelain; ignoring grout compatibility.