To regrout existing tile, first remove about 2mm of old grout with a grout saw or tool, then thoroughly clean and vacuum the dust, apply new, mixed grout with a float at an angle to fill joints, and finally, clean the tile surface with a damp, wrung-out sponge before buffing haze with a microfiber cloth, letting it cure fully.
You generally should not grout directly over old grout for longevity and adhesion, as it often leads to cracking and peeling; instead, you must first remove a significant portion (at least 2mm) of the old grout, thoroughly clean the area, and then apply the new grout to ensure proper bonding and a lasting finish. Special rejuvenation grouts or epoxy grouts might require less removal, but scraping out most of the old material is the best practice for standard grout.
Yes, you generally must remove most of the old grout before regrouting for the new grout to bond properly and last, as new grout won't stick well to old grout, leading to flaking and failure, though some products allow for a minimal 1-2mm depth removal before applying new grout for a refresh. For the best, most durable result, remove the old grout down to the tile's backer board (thinset), clean thoroughly, and then apply the new grout to create a strong, deep bond.
It'll also last longer on the bathroom or kitchen tile floor than in the shower for obvious reasons. So using a grout pen is great way to refresh the color of grout, or even change it from say white to black, but it's not a permanent fix. Granted you can paint over the grout again in few months.
4 of the Most Common Regrouting Mistakes
Working with a Rotary Tool or Oscillating Multi-Tool
Light gray grout maintains a clean and fresh appearance while being more forgiving than white when it comes to stains and discoloration. Darker gray shades, such as charcoal, add depth and richness while effectively masking dirt and algae buildup.
Generally, a well-applied grout pen can last anywhere from six months to a year before requiring a touch-up. In areas with less traffic and moisture, such as backsplashes or accent walls, the application may last even longer.
Using the pen
It's ridiculously easy. Paint over the offending, grubby grout with the pen. That's it. The ink will cover the muck and restore the grout to its sparkling former glory.
The 1/3 rule for tile is a layout technique for long rectangular tiles (like wood-look planks) that recommends staggering joints by one-third of the tile's length, not the traditional 50%, to minimize lippage (uneven tile edges) caused by natural tile bowing, creating a smoother, safer, and more visually harmonious floor or wall. Instead of a standard brick-like pattern, it creates a diagonal or "stair-step" grout line, which looks more natural and helps hide slight height variations between tiles, making the surface feel flatter and more professional, especially under raking light.
Install professional-looking tiles by learning from these common grouting mistakes.
If you're a die-hard DIYer, using Dawn dish soap alone can be a safer option for mild cleaning. Dilute a small amount of Dawn in warm water, scrub the grout with a soft brush, and rinse thoroughly.
epoxy grout is a great choice when you are ready to re-grout a tile project. Because epoxy grout is so much stronger than other types of grout (particularly cement grout), you won't even need to remove all of your old grout. You can apply new grout right over the top of the old grout.
Regrouting tiles is a straightforward job that most confident DIYers can tackle themselves. Take your time when removing the old grout to avoid chipping or damaging your tiles.
Regrouting is the best option when tiles and grout begin to show signs of discoloration or the stains are so deep that they cannot be removed. As grout ages, it naturally deviates from its original color. If the white grout turns yellow or is covered with stains, you must regrout very soon.
EPOXY GROUT
Its superior strength and adhesion properties ensure long-lasting performance, while its easy-to-clean surface maintains its pristine appearance over time. Epoxy grout is the preferred choice for joint filler for tiles where maximum protection against water damage and a professional finish are essential.
Bleach, ammonia, and cleaners with these harsh chemicals added in can cause grout to yellow, fade, or become discolored. They can also degrade the grout and cause it to erode over time.
Since paint is not formulated to be applied to grout, it will not produce a great result. It will sit on top of the surface of your grout lines, and it will not last. Even if it looks okay in the beginning, it will end badly in a short amount of time.
Normally, you need to leave grout for 15-30 minutes before wiping it off. Times vary between products and according to atmospheric conditions in the room. Make sure you read the label for information and keep an eye on the grout while it's drying.
Sealed grout protects it from those outside elements, bacteria growth caused by moisture, and spills that cause staining. Not only that, sealed grout helps strengthen it and slows down the wear and tear process.
Tile and Grout Color Trends for 2025
Expect to see shades like terracotta, sage green, and deep blues in tiles. Grout trends lean toward seamless matching for a clean look or contrasting colors to make the tiles pop. Metallic Grout Finishes: For a modern twist, metallic grout finishes are gaining popularity.
Matching Grout for a Seamless Look
Choosing grout in the same shade as your tile creates one continuous surface, letting the beauty of the tile shine without interruption. This approach is especially effective in smaller rooms, where the seamless look helps expand the feel of the space.
Neutral colors like white, gray, and beige have dominated bathroom tile design due to their versatility. Serving as a clean, minimalist foundation, these colors suit various styles and palettes, ideal for creating a serene environment.