How to Clean Grout Between Floor Tiles

The most effective way how to clean grout between floor tiles is to apply a paste of baking soda and hydrogen peroxide, let it sit for 15 minutes, and then scrub vigorously with a stiff grout brush. For heavy mold or deep discoloration, a commercial alkaline cleaner or a diluted bleach solution works faster. Always remember to apply a grout sealer after cleaning to prevent future staining.

Floor grout gets dirtier faster than wall grout because it’s horizontal – dirt, grime, and moisture all settle directly into it. The good news is that floor grout is usually more durable than bathroom wall grout and can handle more aggressive cleaning methods.

Cleaning Methods by Grout Condition

Step-by-Step: Baking Soda + Hydrogen Peroxide Method

Step 1 – Sweep or vacuum the floor first to remove loose debris.

Step 2 – Make the paste: Mix baking soda with hydrogen peroxide (3%) to form a thick paste.

Step 3 – Apply to grout lines: Spread the paste along the grout with a spatula, old toothbrush, or gloved finger. Work in small sections.

Step 4 – Let sit: 15-20 minutes minimum, longer for stubborn staining.

Step 5 – Scrub: Use a stiff grout brush or a drill-mounted brush attachment for large areas. Scrub along the grout line direction.

Step 6 – Mop and rinse: Go over the whole floor with a damp mop to remove the paste and loosened grime. Follow with a clean water rinse mop.

Tools That Make the Job Easier

• Drill brush attachment – fits a standard drill and covers large floor areas in a fraction of the time
• Narrow grout brush – for precise work in tight or particularly dirty lines
• Steam cleaner – steam penetrates grout pores and loosens buildup without chemicals; very effective for regular maintenance
• Oxygen bleach powder (OxiClean) – mix with water, mop onto floor, let soak 15-30 minutes, then mop off

Bleach Method for Moldy or Black Grout

Mix 1 part chlorine bleach with 4 parts water in a bucket. Apply to grout with a brush, let sit 10 minutes, then scrub and rinse thoroughly. Work in a ventilated area and wear gloves. Never mix bleach with vinegar – this creates toxic chlorine gas. Do not use bleach on colored grout as it will remove the color.

Sealing Grout After Cleaning

After a deep clean, apply a penetrating grout sealer. It fills the pores in the grout and makes future cleaning dramatically easier – grime stays on the surface instead of soaking in. Most sealers are applied with a small brush along the grout lines and take 30-60 minutes to dry. Reapply every 1-2 years.

Final Thoughts

The baking soda and hydrogen peroxide paste handles most floor grout effectively. For mold or severe discoloration, diluted bleach is faster. Sealing the grout after cleaning is the best investment for long-term maintenance – a sealed floor stays clean with basic mopping rather than periodic scrubbing sessions.