Tile + Grout Selection Reference
Why this matters
Tile + grout selection drives durability, aesthetics, + customer satisfaction. Wrong grout on shower floor (sanded where unsanded needed) = visible damage. Wrong tile type in high-traffic area = cracking + wear. Service trades occasionally repair OR replace tile + need to know basics. This is the field card.
Tile types
- Ceramic: glazed clay, indoor wall + light floor, less durable than porcelain, easy to cut.
- Porcelain: higher-fired clay, < 0.5% water absorption, tougher, freeze-resistant (outdoor), floor + wall.
- Natural stone: marble/granite/travertine/slate, premium, requires sealing, higher maintenance.
- Glass: decorative, wall only, mosaic or field tile.
- Metal: decorative accents, wall only, niche.
- Vinyl/LVT: plank/tile look, easier install than ceramic, DIY-friendly.
- Quarry tile: unglazed dense clay, industrial/commercial, floor only.
Tile sizes (common)
Wall: 4x4, 4x6, 6x6, 3x6 (subway), 4x12 (large subway).
Floor: 12x12 (standard), 18x18, 12x24, 24x24 (large format), 6x6 (smaller).
Mosaic: 1x1, 2x2 on mesh sheets.
Subway tile: 3x6 traditional white; many variations now.
Plank tile: 6x24, 9x36, 12x48 (wood look).
Tile install methods
Thinset mortar: cement-based; modified (latex) for most applications, unmodified for natural stone; mix with water (Sakrete, Custom Building, Mapei); notched trowel size matches tile. Mastic (organic adhesive): pre-mixed, wall only (light load), not for wet areas OR floor. Self-adhesive tile: DIY-friendly, limited durability.
Grout types
Sanded grout: sand particles, joint width 1/8" or larger, stronger, texture visible, walls + floors with wider joints. Unsanded grout: no sand, joint less than 1/8" (typically 1/16"), smoother, narrow joints OR delicate tile (glass, marble); don't use sanded on polished surfaces (scratches). Epoxy grout: 2-part (resin + hardener), most durable + stain-resistant, limited working time, more expensive, best for showers + high-traffic. Pre-mixed grout: modified polymer, less durable than cementitious, DIY use mostly. Caulk vs grout: silicone OR sanitary caulk at corners + change-of-plane (movement joints flex; grout cracks); grout for tile-to-tile joints in same plane.
Common tile applications
Bathroom floor: porcelain (durable, water-resistant), 12x12 or 12x24, slip-resistant R 9 - 11, unsanded grout for narrow joints. Shower walls: porcelain or glass mosaic, subway/large format/mosaic, epoxy grout (best wet area). Shower floor: mosaic tile (small for drainage), matte porcelain (slip), epoxy grout. Kitchen floor: porcelain (most common), 12x12 standard, sanded grout, hard porcelain for high-traffic. Kitchen backsplash: subway/mosaic/large format, wall mastic or thinset, unsanded for tight joints. Entryway: slate or porcelain, slip-resistant, sealed (stone). Outdoor: porcelain rated outdoor (freeze-resistant), non-slip, 1/4" joints, sanded grout.
Tile prep + install
Substrate: floor → cement board (Durock, Hardibacker) OR uncoupling membrane (Schluter Ditra); wall → cement board (wet area), drywall (dry area); shower walls → cement board preferred, waterproof membrane. Layout: find center (intersecting diagonals), dry-lay sample row, adjust for cuts (avoid tiny slivers), mark with chalk. Thinset: notched trowel (1/4" × 1/4" small tile, 1/2" × 1/2" large), comb one direction, apply tile within open time (10 - 20 min). Setting: press with slight twist, beat in with rubber mallet (large tile), check level + plumb, use spacers (1/16", 1/8", 1/4"). Grouting: wait 24 - 48 hr for thinset cure, mix to peanut butter consistency, apply with rubber float at 45°, pack joints, wipe diagonal with damp sponge, multiple passes + clean water between. Cure: 72 hr light traffic, 7 days full cure, seal grout (if cementitious) after cure.
Specialty installations
Curbless shower: linear drain, floor sloped 1/4" per ft, continuous floor bathroom-to-shower, tile + drain integration critical. Heated tile floor: electric mat OR water hydronic under tile, thermostat control, premium feature. Schluter system: uncoupling membrane (Ditra), waterproof membrane (Kerdi), edge profiles, premium installations.
Tile cutting
Wet saw: most accurate; runs water for dust + cooling.
Snap cutter: scores + breaks; OK for ceramic.
Angle grinder w/ diamond blade: for cuts in place.
Tile nipper: small irregular cuts.
Diamond hole saw: for round holes (drain, pipe).
Grout color
Match to tile: most professional look.
Contrast for accent: dark grout with light tile (or vice versa).
Light grout: shows stains more.
Dark grout: hides stains; can absorb into porous tile (test first).
Pigment fade: some cementitious grouts fade in sun; check warranty.
Grout sealing
Cementitious grout is porous; absorbs liquid + stains. Seal 7 - 14 days after install (after cure), after deep cleaning, + annually for heavy-use areas. Penetrating sealer absorbs into grout (invisible); topical sealer forms surface film (can yellow). Don't seal epoxy grout - not porous.
Common tile + grout mistakes
Wrong grout for joint width (sanded in narrow = pinholes; unsanded in wide = cracking). Sanded on polished surface scratches tile. Grout cracking at corners needs flexible caulk at change-of-plane. Insufficient thinset coverage (tile lifts; need 90%+ contact wet area, 80% dry). Wrong notched trowel (too small = no contact; too large = excess). Skipping shower waterproofing leaks. Sealing too early (grout still curing; sealer doesn't bond). Wrong mortar for substrate (thinset doesn't bond to drywall; need backerboard). Skipping cure before grouting (tiles shift). Skipping cleanup during install (thinset hardens; can't remove later).
Repair work
Cracked tile: remove damaged tile (carefully break + chip), clean substrate, apply new thinset, set new tile, wait + regrout, 24 hr no traffic. Discolored grout: clean (grout brush + cleaner), re-color (grout colorant), OR remove + replace (grout saw). Loose tile: likely substrate movement OR water damage; diagnose root cause, repair substrate, re-set tile.
Truck stock (for repair work)
Common thinset bags (mid-grade modified), common grout (white + gray, sanded + unsanded), notched trowels (3 sizes), rubber float, manual snap tile cutter, spacers (1/16, 1/8, 1/4), diamond hole saws (1, 1-1/4, 1-1/2 for plumbing), painter's tape, damp sponge + bucket.
The single most-important tile habit is the SANDED-FOR-LARGE-JOINTS, UNSANDED-FOR-NARROW-JOINTS rule. Tile joint less than 1/8" requires unsanded grout (sanded won't pack in). Joint 1/8" or larger requires sanded (unsanded would crack). Polished surfaces (glass, marble) REQUIRE unsanded regardless of joint width (sand would scratch). The single biggest grout-job mistake is using sanded grout where unsanded was needed; the joints look pitted + customer's job looks unprofessional.
References
- TCNA (Tile Council of North America) Handbook
- ANSI A108 + A118 (tile install standards)
- Manufacturer technical data (Mapei, Custom Building Products, Laticrete)
- Manuall internal: Sealant + Caulk Selection, Adhesive Selection Materials