Your grey grout turns yellow due to trapped dirt, soap scum, body oils, or mildew, but also from mineral deposits from hard water (iron/calcium), incorrect cleaning products (like bleach/vinegar), or minerals bleeding from unsealed stone tiles (like marble). Iron oxidation from the water or rust from nails behind tiles can also cause yellow/brown stains, often exacerbated by excessive moisture.
In many instances when the grout has become permanently stained and no amount of cleaning can bring back the original uniform clean look of the grout. In these cases, it is best to apply Universeal Grout Rescue Colour & Seal to restore the grout to a permanently sealed even coloured finish.
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.
Magic Erasers are great for cleaning grout. They lift dirt with very little effort, even from this usually impossible site. However, the grout will eat through your Magic Eraser fast. If you're touching up the grout in a small portion of your backsplash, using Magic Erasers is perfect.
Professionals use a multi-stage approach for cleaning grout, combining alkaline degreasers, steam cleaning, and high-pressure hot water extraction for deep cleaning, often using specialized brushes and sometimes acid washes for tough stains, plus tools like grout brushes, microfiber cloths, and sometimes powerful machine scrubbers for large areas, always ending with thorough rinsing and drying. They might also use oxygen bleach for brightening or specific grout cleaning powders for tough discoloration.
The process is exactly the same: First, mix some baking soda with water to form a paste (a ratio of three parts water to one part baking soda is usually recommended), then apply this to the grout and rinse it away after it has had time to work its magic.
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.
It is generally cheaper to regrout than to retile. Regrouting costs an average of $700–$1,500 while retiling costs $1,800–$5,000 on average.
While grout pens are not a permanent solution to some grout issues, they're still an affordable and easy way to help you transform your home. Just be sure that you choose a grout pen in a color that works for your style, the room itself, and the tile.
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.
4 of the Most Common Regrouting Mistakes
The biggest culprits are mould and mildew, which can turn your grout an unpleasant grey colour, but a build-up of shampoo and shower gel can also turn your bathroom grout an unappealing shade of yellow or orange.
The Pink Stuff
Simply rub and scrub, and then rinse with hot water. As a mildly abrasive cleaner, the paste has a little grit to it, which helps scrub away dirt and debris from grout and surfaces.
Diluting the hydrogen peroxide to a 1:1 ratio with water will ensure a safe but effective concentration. Here's a simple, proven method to clean grout safely while preventing long-term damage. Prepare the Cleaning Solution. Mix equal parts hydrogen peroxide (3%) and warm water in a spray bottle.
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.
Yes, you can remodel a bathroom for $5,000, but it requires focusing on cosmetic updates (paint, fixtures, lighting, accessories) rather than major structural changes (moving walls, plumbing, or enlarging spaces), often involving significant DIY work for tasks like tiling, painting, and vanity refinishing to keep costs down. Expect to refresh the look with new finishes, potentially resurface existing tubs/tiles, update hardware, and do the labor yourself to stay within budget, as major replumbing or electrical work will quickly exceed $5,000.
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.
Avoid these 9 common grouting mistakes that could be ruining your tiling projects
How often does grout need to be sealed?
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.
I want to actually clean my grout. Magic erasers get the job done, and they do it quickly and relatively painlessly. Technique-wise, I usually cut my standard size magic eraser in half, wet it to slightly more than damp, and scrub the grout line as I squeeze gently.
To prevent various types of damage, below are some of the things you should avoid using when cleaning grout.
Cleaning grout with household remedies step-by-step