How to Troubleshoot Bathroom Tile Grouting Issues at Home

Quick answer (read this first)

• Identify grout issues like cracks, discoloration, or mold.
• Thoroughly clean and remove damaged grout.
• Mix and apply new grout correctly.
• Allow new grout to cure completely before sealing.
• Ensure good ventilation to prevent future problems.

Safety first

• Wear safety gloves and eye protection when working with chemicals.
• Ensure good ventilation in the bathroom during the process.
• Use tools carefully to avoid damaging tiles or injuring yourself.
• Keep children and pets away from the work area and chemicals.

Tools you may need

• Grout saw or grout removal tool
• Utility knife
• Grout float
• Sponge and bucket
• Grout cleaner or mild bleach solution
• New grout (sanded or unsanded, depending on gap size)
• Grout sealer (optional)
• Safety gloves and eye protection

Step-by-step

Step 1

Inspect Grout Thoroughly: Carefully examine all grout lines for signs of damage, including cracks, crumbling, discoloration, persistent mold, or mildew growth.

Step 2

Clean Affected Areas: Apply a suitable grout cleaner or a mild bleach solution to discolored or moldy areas. Scrub vigorously with a brush to remove grime and prepare the surface.

Step 3

Remove Old Grout: Using a grout saw or specialized removal tool, meticulously scrape out all damaged, loose, or crumbling grout. Work slowly to prevent chipping or scratching adjacent tiles.

Step 4

Prepare Tile Gaps: After removing old grout, vacuum or wipe away all dust and debris from the tile gaps. Ensure the area is completely dry before applying new grout for optimal adhesion.

Step 5

Mix New Grout: Follow the manufacturer’s instructions precisely to mix your chosen grout. Achieve a smooth, consistent, peanut butter-like texture, adding water gradually to avoid a runny consistency.

Step 6

Apply New Grout: Hold a grout float at a 45-degree angle and firmly press the freshly mixed grout into the tile lines. Work in small sections, ensuring all gaps are fully packed without voids.

Step 7

Clean Excess Grout: After the recommended set time (check grout packaging), gently wipe off excess grout from tile surfaces using a damp sponge. Rinse the sponge frequently for a clean finish.

Step 8

Cure and Seal Grout: Allow the new grout to cure completely according to the manufacturer’s guidelines, typically 24-72 hours. Once dry, apply a high-quality grout sealer for added protection against moisture and stains.

Common mistakes

• Not completely removing all old, damaged grout.
• Improperly mixing new grout, leading to a weak bond or cracking.
• Applying new grout to a wet or dirty surface.
• Waiting too long to wipe off excess grout from tiles.
• Using the wrong type of grout (e.g., unsanded for wide gaps).
• Not allowing sufficient curing time before exposing to water.

When to call a professional

• If you notice extensive underlying water damage or persistent leaks.
• When multiple tiles are loose, cracked, or falling off.
• If you are unsure about the root cause of recurring grout issues.
• For widespread mold or mildew problems that are difficult to eradicate.
• If the issue might involve structural damage or plumbing leaks behind the walls.