If your grout was never properly sealed, it will be more prone to absorbing and showing discolorations. The most common culprits for grout stains are spills, cleaning residue, and mold/mildew build-up. The best way to avoid this is to clean regularly and with proper cleaners.
Blotchy grout colors are usually the result of too much water used somewhere during installation or cleanup process. Sometimes discoloration can occur due to minerals suspended or dissolved in the water used to mix the grout, insufficient mixing (uneven pigment distribution), or using grout that's past its shelf life.
Use a commercial grout cleaner or a homemade solution of equal parts white vinegar and water in a spray bottle. Spray the grout lines generously with the cleaner. Scrub with a Brush: Scrub the grout lines with an old toothbrush or a grout brush. Use a back-and-forth motion to loosen dirt and stains.
Blotchy grout colors are usually the result of too much water used somewhere during installation or cleanup process. Sometimes discoloration can occur due to minerals suspended or dissolved in the water used to mix the grout, insufficient mixing (uneven pigment distribution), or using grout that's past its shelf life.
To remediate this type of problem to make the grout to be more consistent in color there are products called "grout colorants" that are epoxy based and match some of the typical grout colors. After properly preparing the existing grout joint you paint it over the joint which could be a bit tedious of a process.
Some professionals swear by a simple mixture of baking soda and peroxide to clean grout. Hydrogen peroxide is an acid, and baking soda is a base compound. Mixing the two together creates a reaction that can penetrate the grout lines and free dirt and debris.
The most effective and simple way to clean your grout is using distilled white vinegar mixed with water. If the grout is heavily stained and requires lightening, you may decide to first apply bicarbonate of soda paste before you begin cleaning.
Re: Removing grout haze
I'd suggest using a 50/50 mix of white vinegar and water. Please make sure to flush the area down with fresh water after your attempt.
It is highly recommended to remove your old and damaged grout before applying new grout.
To mix homemade grout cleaner all you will need is blue dawn and warm to hot water. You will start by pouring a dime-sized squirt of blue dawn into a trigger bottle (preferably a 32-ounce bottle). Make sure the spray can be adjusted to stream and not spray. Then fill with water and lightly shake.
Clean grout with a commercial grout and tile cleaner. Apply it to the dirty areas of the grout following the manufacturer's instructions. If you prefer cleaning grout with a DIY mixture, make a paste of 3/4-cup baking soda, 1/4-cup hydrogen peroxide and 1 tablespoon of mild dish soap.
Mildew can often show up as a yellowing of grout. Mold and mildew are fungal growths that thrive in damp and humid environments, while Serratia marcescens is a bacterium that is responsible for the pink or reddish-pink discoloration on grout and other surfaces.
Damp showers produce brown grout even more than other areas
You might notice that your grout turns brown much quicker in your shower than any other area of your home. This could mean that mold spores and mildew are setting up deep within your grout.
Chemical cleaners, such as, Tilex, Soft Scrub, Scrubbing Bubbles, or ammonia products will nearly always result in your tile surfaces' grout becoming very discolored.
If dirt and grime are simply coating the surface of your grout, simply sweep and damp mop to remove the discolorations. If the grout lines still look dark, it is because the pores in the grout are filling up with contaminants again, and those contaminants have seeped down below the surface.
For floors, steam mops are highly effective for cleaning grout. Just like the handheld steam cleaner we tested, a steam mop can clean and sanitize your tile and grout without resorting to harsh chemicals.
If you're trying to clean grimy grout between your bathroom shower or floor tiles, then OxiClean™ bathroom cleaners are here to help! They get rid of grout stains on vertical and floor tiles for a refreshed bathroom.
It's best to try rinsing your grout with plain water and a gentle cleanser like dish soap. If this doesn't work, before you decide to use a cleaner across your surface, test it on a small section of your grout. We recommend starting with a dedicated grout cleaner before trying to deep clean.
While white vinegar is a popular and effective cleaning solution for tiles, it can damage certain tiles and grout if used improperly or frequently. White vinegar is an acidic solution that can etch or corrode some tiles, particularly those made from natural stone or unglazed ceramic.
Tiles and grout
One of our favourite ways to use The Pink Stuff is to revive tired and grubby tiles. Work it into the grout with a sponge or an old toothbrush and you'll be amazed at how much you can brighten up those old bathroom or kitchen tiles.
Cleaning grout with vinegar is a popular solution to keep your bathroom shiny. Create a solution of half water and half white vinegar – you could also use brown vinegar, but it tends to have a stronger smell which you may not wish to have anywhere besides your chips.