How Do I Grout Tile?
Topics
- Grout
- Tile
- Installation
- Flooring
- Bathroom
Answer
Grouting is the final step in a tile installation — and rushing it is the most common way to ruin an otherwise perfect tile job. The key rules: right grout type, right timing, right clean-up.
Choose the right grout
- Unsanded grout: for joints under ⅛ inch (most wall tile, mosaic, glass tile)
- Sanded grout: for joints ⅛ inch and larger (floor tile, most large-format tile)
- Epoxy grout: most durable, stain-resistant, and expensive — best for commercial or high-abuse areas
- Color match: take a tile sample to the store and compare under natural light
Timing
Wait at least 24 hours (preferably 48) after setting tile before grouting. The thinset must cure fully. Grouting over wet thinset traps moisture and causes grout to crack.
Mixing
Mix grout with water (or latex additive) to a peanut butter consistency. Mix for 3 minutes, let "slake" for 5–10 minutes (this activates polymers), mix again briefly. Don't add more water after slaking — this weakens the grout.
Application
Hold the float at 45° and spread grout diagonally across the joints. Press firmly to pack the joints completely. Work in 3–4 square foot sections. Remove excess grout by holding the float at a steeper angle and wiping diagonally across the joints.
Clean-up (the critical part)
Wait 15–20 minutes (until a haze appears on the tiles but grout in joints is still soft). Wipe with a damp sponge, wringing it out frequently. Circular motions first, then straight passes to flatten the joint surface. Multiple light passes are better than one hard scrub.
After the final clean, a grout haze remains on tile faces. Once grout is cured (24 hours), wipe with a dry microfiber cloth — the haze buffs off easily at this stage.
Sealing
Seal sanded grout and unpolished natural stone with penetrating sealer 72 hours after grouting. Unsanded grout and polished tile typically don't need sealing. Re-seal annually in wet areas.
Related Guides
Ask About Your Project
ChatDIY can turn this answer into a project-specific plan with measurements, tool checks, and next steps.