How to Troubleshoot Kitchen Tile Grouting Issues at Home

Quick answer (read this first)

• Regularly inspect grout for cracks or discoloration.
• Clean affected areas thoroughly before repairs.
• Choose the correct grout type and use appropriate tools.
• Apply new grout meticulously and remove excess promptly.
• Always seal newly repaired grout to prevent future moisture damage.

Safety first

• Wear gloves and eye protection when handling cleaning chemicals or grout.
• Ensure good ventilation in the kitchen while working.
• Avoid direct skin contact with grout and cleaning solutions.
• Keep children and pets away from the work area until it’s clean and dry.

Tools you may need

• Grout saw or utility knife
• Stiff brush or scrub pad
• Grout cleaner (optional, for stubborn stains)
• Bucket
• Sponge
• New grout (sanded or unsanded, depending on joint size)
• Grout float
• Grout sealer
• Safety goggles
• Rubber gloves
• Vacuum cleaner

Step-by-step

Step 1

Step 1: Assess Grout Damage. Carefully examine all kitchen tile grout lines for cracks, crumbling, discoloration, mildew, or missing sections. Identify all areas needing repair.

Step 2

Step 2: Initial Cleaning. Use a stiff brush or scrub pad with warm water and mild detergent to clean the surface of the affected grout lines and surrounding tiles.

Step 3

Step 3: Deep Clean (If Needed). For stubborn stains or extensive mildew, apply a dedicated grout cleaner following product instructions. Rinse thoroughly and allow the area to dry completely before proceeding.

Step 4

Step 4: Prepare for Grout Removal. Don safety goggles and rubber gloves to protect yourself.

Step 5

Step 5: Remove Damaged Grout. Using a grout saw or utility knife, carefully scrape out the old, damaged, or discolored grout. Work slowly to avoid chipping or scratching the tiles. Aim to remove at least two-thirds of the old grout depth for proper adhesion of new grout.

Step 6

Step 6: Clear Debris. Vacuum or brush away all removed grout particles and dust from the gaps. Ensure the grooves are clean and dry for optimal new grout bonding.

Step 7

Step 7: Choose Correct Grout Type. Select sanded grout for wider joints (1/8 inch or more) and unsanded grout for narrower joints (less than 1/8 inch).

Step 8

Step 8: Mix New Grout. In a clean bucket, mix the new grout powder with water precisely according to the manufacturer’s instructions. Achieve a consistent, paste-like texture, free of lumps, similar to peanut butter. Let it sit for 5-10 minutes (slaking) then re-stir.

Step 9

Step 9: Apply Grout. Scoop a small amount of mixed grout onto a rubber grout float. Holding the float at a 45-degree angle, firmly press the grout into the tile joints, ensuring they are completely filled and packed tightly. Work in small sections.

Step 10

Step 10: Remove Excess. After filling a section, use the float at a nearly 90-degree angle to scrape off excess grout from the tile surface, pulling it diagonally across the joints.

Step 11

Step 11: Initial Grout Haze Removal. Wait 10-20 minutes for the grout to set slightly. Using a lightly damp sponge, gently wipe the tile surface in a circular motion to remove the initial grout haze. Rinse the sponge frequently with clean water.

Step 12

Step 12: Final Wipe-Down. After another 15-30 minutes, or once the grout has hardened a bit more, perform a final wipe-down with a clean, damp sponge to remove any remaining haze and smooth the grout lines. Be careful not to pull grout out of the joints.

Step 13

Step 13: Allow Grout to Cure. Let the newly applied grout cure completely according to the manufacturer’s instructions, typically 24-72 hours. Avoid exposing it to water or heavy use during this period.

Step 14

Step 14: Apply Grout Sealer. Once the grout is fully cured and dry, apply a high-quality penetrating grout sealer to protect it from moisture, stains, and mildew. Follow the sealer’s instructions for application and reapplication frequency.

Common mistakes

• Not properly cleaning the old grout before applying new, leading to poor adhesion.
• Mixing grout incorrectly (too watery or too thick), affecting its strength and appearance.
• Applying new grout over existing loose or moldy grout instead of removing it.
• Not waiting for the proper curing time before cleaning or applying a sealer.
• Using the wrong type of grout (e.g., unsanded for wide joints or vice versa).

When to call a professional

• If you discover extensive mold or mildew growth that persists after cleaning or reappears quickly.
• If multiple tiles are loose, cracked, or if you suspect underlying structural damage to your subfloor or walls.
• If there are signs of water leakage or moisture issues behind the walls or under the floor, indicating a larger plumbing problem.
• If you feel uncomfortable or lack the specific tools and experience for proper grout removal and application.
• For large-scale kitchen renovations that involve extensive re-grouting and tile work beyond simple spot repairs.