Grout serves an important purpose in tiling by filling in the spaces between tiles to create a waterproof surface. Over time, grout can become discolored, making tile floors and walls look dirty and dingy. Replacing all the grout can be expensive and time consuming. Luckily, there are inexpensive and effective methods using common household items that allow you to clean and restore grout to like-new condition.
Why Grout Gets Dirty
Grout is porous, which allows it to absorb liquids, dirt, grime and stains over time. Common causes of grout discoloration include:
- Mold and mildew growth
- Spills and splatters from food, grease, oil, etc.
- Soap scum buildup in bathrooms
- Mineral deposits from hard water
- Ground-in dirt and foot traffic
Discoloration occurs gradually as the grout takes in these contaminants. The effect is grout lines that look dark, stained and grubby.
Cleaning vs. Re-Sealing Grout
It’s important to know whether your discolored grout just needs a good cleaning or if it also requires re-sealing. Sealer is applied to grout lines to make them more stain-resistant. Over years of use, this protective seal can wear away due to cleaning, abrasion and exposure to moisture.
Signs that your grout needs to be re-sealed:
- Grout has absorbed stains that don’t clean off
- Damp grout appears darker than dry grout
- Grout seems porous when you apply water to it
Tips for cleaning and re-sealing grout:
- Clean grout first before applying new sealant
- Use sealant made specifically for grout
- Follow product directions carefully for drying time before using shower/tub
Household Cleaners That Restore Grout
Many common household products can be used to effectively remove dirt, stains, soap scum and muck from grout lines. Using items already under your kitchen or bathroom sink can save a lot of money compared to specialized grout cleaners.
Baking Soda
Baking soda is mildly abrasive and alkaline, which makes it great for scrubbing away grime and discoloration on grout.
How to use:
- Make a paste by mixing 3 parts baking soda to 1 part water.
- Apply paste to grout lines and let sit for 5 minutes.
- Scrub with a stiff grout brush or old toothbrush.
- Rinse thoroughly with water.
Repeat as needed for heavily soiled grout. Baking soda can help remove stains from grease, mold, mildew and mineral deposits.
Hydrogen Peroxide
The bubbling reaction of hydrogen peroxide can help lift stains and discoloration out of grout pores.
Application:
- Pour 3% hydrogen peroxide directly onto grout lines.
- Let sit for 10-15 minutes as foam develops.
- Scrub with a stiff scrub brush and rinse well with water.
Hydrogen peroxide is effective at whitening grout stained by mold and mildew.
Vinegar
The high acidity of vinegar breaks down mineral deposits, soap scum, hard water stains and other grime.
Cleaning method:
- Use undiluted white vinegar and pour directly onto grout.
- Let sit for 15 minutes.
- Scrub with a grout brush.
- Rinse thoroughly with water.
For tougher stains, combine equal parts vinegar and baking soda for improved cleaning action.
Lemon Juice
Like vinegar, lemon juice contains acidic compounds that can dissolve mineral deposits and soap scum on grout.
How to clean grout with lemons:
- Squeeze fresh lemon juice onto grout lines.
- Let juice sit for 10 minutes.
- Scrub with a brush or sponge.
- Rinse thoroughly.
The bleaching powers of lemon can also brighten dingy, discolored splotches on grout.
DIY Grout Cleaning Recipes
For heavy duty grout cleaning, you can mix up DIY cleaners using items from your pantry. These homemade mixes can tackle tough stains and rejuvenate badly discolored grout.
Baking Soda and Vinegar Grout Cleaner
This mixture produces a chemical fizzing reaction that penetrates deep into grout.
Ingredients:
- 1/2 cup baking soda
- 1/4 cup white vinegar
- 1/4 cup warm water
Directions:
- Stir baking soda and vinegar together in a bowl until fizzing stops.
- Add water and mix into a thick paste.
- Spread paste onto grout and let bubble for 10 minutes.
- Scrub and rinse.
Repeat as needed for heavy grime.
Hydrogen Peroxide and Baking Soda Grout Cleaner
This combination whitens and deodorizes grout. The baking soda gives a gentle abrasive scrubbing action.
What you’ll need:
- 1/2 cup hydrogen peroxide
- 1/4 cup baking soda
- 1 tablespoon liquid dish soap
How to mix and apply:
- In a bowl, combine ingredients into a frothy paste.
- Apply to grout lines and let sit 20 minutes.
- Scrub with a stiff bristle brush.
- Rinse clean.
Use rubber gloves when cleaning with this mixture, as prolonged exposure can dry out skin.
Grout Brush Techniques
Having the right grout brush makes all the difference when scrubbing narrow grout lines. Look for these features in a good grout brush:
- Stiff bristles
- Thin bristle head
- Handle for gripping
Tips for grout brush cleaning:
- Apply cleaner and let soak before scrubbing
- Use short, repeated back-and-forth motions
- Rinse brush often while scrubbing
- Clean entire grout line, not just surface
- Rinse cleaned sections immediately
Avoid using wire-bristle brushes, which can scratch grout. An old toothbrush works in a pinch for grout detail work.
Whitening Grout With Bleach
For grout discolored beyond normal cleaning, bleach can help whiten and brighten grout back to like-new.
Caution: Never mix bleach with vinegar, hydrogen peroxide or other acids—this creates toxic chlorine gas.
How to safely use bleach on grout:
- Use only plain bleach without added cleaners
- Dilute bleach 50/50 with water
- Work in a ventilated room
- Apply diluted bleach and let sit 10 minutes
- Scrub and rinse thoroughly
- Repeat as needed
Bleach can eat away at and discolor colored grout, so spot test first. Make sure to rinse away all bleach residues.
Preventing Grout Stains Recurrence
After putting in the elbow grease to get grout sparkling clean, you’ll want to keep it that way. Here are tips to prevent future discoloration and extend time between deep cleans:
- Sweep or vacuum tile floors often to prevent ground-in dirt
- Use floor mats at entryways to trap dirt and moisture
- Seal grout every 1-2 years per manufacturer directions
- Spot clean spills and splatters quickly
- Maintain bathroom ventilation during and after showering
- Use grout-coloring sealant on badly stained grout for like-new appearance
With routine light cleaning and the right household products, you can keep your grout lines looking fresh and clean. A little periodic heavy-duty cleaning will take care of any set-in stains.
