IICRC SMT cheat sheet

Classify stone before specifying chemistry: calcite-based stones (marble, travertine, limestone, onyx) are acid-sensitive; siliceous stones (granite, quartzite, slate, sandstone) tolerate mild acid but not strong alkali or fluoride salts.

pH rule: keep cleaning solutions for calcite stones within roughly pH 6-8 neutral range; any acid (vinegar, citric, sulfamic, acidic grout cleaners) etches calcium carbonate and dulls polish permanently.

Water absorption by stone type drives sealing decisions: granite typically under 0.5 percent, marble 0.2-0.5 percent, limestone and sandstone often 2-6 percent; higher absorption means higher risk of staining and freeze damage.

Impregnating sealer chemistry: solvent- or water-based siloxane/silane penetrants line the pore walls and allow vapor transmission; film-forming coatings (waxes, acrylics) trap moisture and are inappropriate for most stone floors.

Test every chemical in an inconspicuous area for 24 hours; check for etch (surface dulling on calcite stone), color change, and residue before full application.

Etch removal on polished marble requires repolishing with abrasives (diamond or polishing powder), not chemical cleaning; a dark "ring" that will not clean off is likely etch, not soil.

Efflorescence on stone and masonry is migrated soluble salt; dry-brush or use a mild acidic salt remover only on acid-tolerant stone, then correct the moisture source or it returns.

Diamond abrasive sequence for restoration moves coarse to fine (for example 50-100-200-400-800-1500-3000 grit) with each step removing the scratch pattern of the previous grit; skipping grits leaves visible scratches.

Drying matters: standing water on limestone, travertine, and some marbles causes spalling, picture-framing, or staining; use low-moisture methods and rapid extraction with air movement.

Engineered quartz is roughly 90-95 percent ground quartz with polyester or epoxy resin binder; the resin matrix limits heat tolerance, so high-alkali strippers and strong solvents can dull or discolor the surface.

Cultured marble and onyx are typically ground calcium carbonate filler in a polyester resin; they are acid-sensitive like natural marble, so acidic cleaners etch the gel coat and dull the finish.

Solid surface (e.g., acrylic/polyester blends) is non-porous and renewable: light abrasion with a Scotch-Brite-type pad followed by progressively finer pads restores a matte or satin sheen.

Most engineered and cultured stone surfaces are non-porous and do not need penetrating sealer; applying sealer can leave a film or haze that attracts soil.

Avoid bleach, ammonia, and high-pH degreasers on resin-based products; residue can cause yellowing, chalky film, or loss of gloss under UV exposure.

Heat rule: place hot pans on trivets; quartz and cultured products can scorch, crack, or craze from thermal shock at roughly 150 C (300 F) and above.

Gel-coat scratches on cultured marble can be polished out with fine abrasives and compound; deep gouges that expose filler require a repair kit matched to the base resin color.

Grout joints around engineered slabs are usually the only porous element; seal the grout, not the slab, and clean joints with a soft brush to avoid scratching the polished face.

Porcelain water absorption is typically 0.5 percent or less and is frost- and stain-resistant; non-porcelain ceramic (quarry tile, glazed wall tile) absorbs more and may need sealing at the body or grout.

Glazed tile cleaners must be non-abrasive and near-neutral; abrasive powders and pads dull glaze and open micro-scratches that hold soil.

Unglazed quarry tile and through-body porcelain tolerate stronger alkaline degreasers and mechanical agitation because there is no glaze to damage.

Acid products (sulfamic, phosphoric, hydrochloric blends) are for grout haze and mineral deposits only; never use hydrochloric acid on glazed tile, cement grout, or any surface containing calcium carbonate.

Slip resistance: wet tile is a safety hazard; measure with a tribometer and note that coefficient of friction drops as soil, soap scum, and sealer films accumulate.

Tile-and-grout cleaning sequence: dry removal of loose soil, pre-spray dwell, agitation with a brush or pad matched to the surface, then high-pressure extraction and dry stroke to remove suspension.

Efflorescence and latex migration on new tile installations are construction residues; remove with appropriate remover after the grout cures, not during the initial wash-down.

Cementitious grout is porous and cement-based; epoxy grout is non-porous and chemical-resistant, so solvent and acid selection must match grout type, not just tile type.

Masonry substrates include brick, concrete block, mortar, stucco, and stone; each has different porosity and acid tolerance, so test a small area before specifying a cleaner.

Mortar joint sand and cement are the weak point: excessive pressure (generally above 800-1200 psi on soft brick or mortar) erodes joints and opens pathways for water intrusion.

Efflorescence is water-soluble salt carried to the surface by moisture; removal is mechanical or mild acid, but recurrence indicates an active moisture path that must be corrected.

Grout sealing: cementitious grout benefits from a penetrating sealer after full cure (typically 72 hours for cement grout); epoxy grout generally does not require sealing.

Grout cleaning chemistry: alkaline detergents for grease and organic soil; acidic cleaners for mineral haze and efflorescence; never mix acid with bleach or ammonia.

Color sealing (grout coating) is an option when grout is stained or eroded; it requires a clean, dry, neutralized surface and full cure before use.

Brick cleaning: use low-pressure, high-volume rinse with a neutral or mild alkaline cleaner; muriatic acid is reserved for stubborn mortar smears on acid-tolerant clay brick and requires PPE and neutralization.

Waterproofing and vapor management: masonry walls and slabs need drainage and vapor control; sealing the surface without addressing moisture can trap water and cause spalling or mold.

Inspection checklist before cleaning masonry: identify efflorescence vs. mold vs. dirt, check for spalling and cracked joints, verify weep holes are clear, and document existing damage with photos.