How to Change Grout Color

Grout starts out looking clean and tidy, but eventually, it starts to show its age. It can discolor, degrade, or simply no longer fit with your interior design. When that happens, there’s an often-overlooked fix you should consider: changing grout color. Here’s how to do it. 

Why Should I Change My Grout Color?

Coloring grout is a great way to update the look of a tile job without committing to a more extensive (and expensive) renovation. It can also cover up the inevitable stains and mildew spots that crop up over time. If your grout looks dingy and dirty even after you’ve just cleaned it, changing the color can make it look fresh again.

If you choose a darker grout color, it can hide future stains, making it easier to maintain the grout’s appearance.

You have two choices when it comes to changing grout color: You can apply a colorant, or you can remove and replace the grout.

How to Prep for Changing Grout Color

When looking at how to change grout color, you can’t forget preparation. Here’s a look at the prep work required, whether you choose to repaint your existing grout or remove and replace it. 

Prep for Repainting Grout

Repainting or staining grout works well if you’re darkening the grout or if you’re working with smooth tiles. Preparation involves thoroughly cleaning the grout and tile. Grout colorants may require specific cleaning products for the best results, so check the manufacturer’s instructions.

Generally speaking, applying white vinegar and a paste made from baking soda and water using a stiff scrub brush works well. Scrub, then rinse the area with a sponge and water. Let the tile and grout dry completely before repainting.

After cleaning, test the colorant on a small area by:

• Shaking the colorant bottle to mix the contents

• Applying a small amount of colorant on an inconspicuous area, using a sponge or brush 

• Letting the colorant dry to a hard finish 

• Lightly scrubbing the grout to ensure the stain will hold

If the paint or stain flakes off, you might need to try a different product to find one that works with your existing grout. 

Prep for Removing and Replacing Grout

Use this method for coloring grout when:

• You’re working with natural tiles, which are especially porous (meaning they’ll readily absorb grout colorant).

• You want to lighten the grout color.

• You need to remove mold or mildew from the grout.

Preparation for removing and replacing grout includes donning protective gear, including safety glasses, a mask, and gloves. You also need to cover the work area with plastic sheeting or a drop cloth.

How to Change Grout Color

Of the two grout coloring techniques, the repainting/staining method is the easiest and quickest. It’s also the least expensive. However, both methods require at least a few supplies, so make sure you have everything on hand before you start.  

Repaint Existing Grout

This simple process doesn’t take an experienced DIYer, but you do need to have your tools and supplies on hand, which include:

• Mixed colorant (shake to mix)

• Stiff brush

• Grout coating pen (optional)

• Nylon sponge

• Sealant (optional)

With everything at hand, you’re ready to revitalize your grout using the following steps.

1. Tape the Tile Surfaces (Optional)

While this step is optional, it’s a good idea if you have unsealed tiles or if you’re worried about staining the tiles. Use painter’s tape to tape off the tile in small sections as you work through the space. Working in sections prevents the colorant from drying before you can wipe it off.  

2. Apply the Colorant with a Small Stiff Brush or Grout Coating Pen

Apply the colorant using a small stiff brush, like a toothbrush. You can also use a grout-coating pen. These pens are best for small areas, but they are a cost-effective solution for the right project. 

3. Work the Colorant Into the Grout

The colorant needs to penetrate the grout’s pores. Rub vertically and horizontally to get it fully integrated into the grout. 

4. Remove Excess Colorant

While the colorant is still wet, wipe off any excess from the tile surface using a nylon sponge. A well-glazed tile can resist the colorant for a couple of hours, but it’s best to be on the safe side and wipe away the excess as soon as possible. If you have textured tiles, you may need to mist the tile’s surface to fully remove all of the colorant.

5. Let the Colorant Dry

Let the colorant dry according to the manufacturer’s directions. Times will vary, but most dry within a few hours. The area shouldn’t be used until the colorant has fully dried.

6. Apply a Secondary Sealer (Optional)

Many grout colorants contain a sealer, eliminating the need to apply an additional sealer. However, some colorants are pure dyes and will require a sealant after they’ve completely dried. The sealant protects the color and makes the grout darker and shinier. 

Replace Existing Grout

Replacing grout is a more involved process, but it gives you more color options and offers a chance to improve the durability of the grout. You need a few more tools and supplies for this method, including:

• Oscillating tool

• Flat-blade screwdriver

• Utility knife

• Vacuum

• Flat nozzle for vacuum

• Stiff-bristled brush

• Grout powder 

• Pre-mixed grout (optional)

• 2-gallon bucket

• Grout colorant

• Trowel

• Grout float

• Nylon sponge

• Microfiber cloths

• Grout sealant

After donning protective gear, follow these steps:

1. Remove the Old Grout

Remove the old grout using an oscillating tool, manual grout saw, or multi-tool with a tile blade. 

Clean the tile edges to remove excess grout using a flat-blade screwdriver and utility knife. You need to create at least a ⅛-inch joint space for the new grout to penetrate and adhere correctly.

2. Inspect the Tiles

Gently tap the tiles with the plastic handle of a screwdriver. A hollow sound indicates a weak connection between the tiles and the substrate. Replace any tiles that are weakly adhered; you’re more likely to encounter this issue if you’re removing crumbly grout.

3. Clean the Grout Joints

Use a stiff-bristled brush and a vacuum outfitted with a flat nozzle to remove debris and loose grout from the joints. Proper grout adhesion requires a clean surface, so be thorough.

4. Mix the Grout

Check that the new grout is compatible with and can bond with the old grout by reading the manufacturer's recommendations. Mix the grout according to the manufacturer's instructions; be sure to let it rest for 10 minutes so the chemicals can fully activate before application. You can save time by using pre-mixed grout. 

5. Add Grout Colorant (Optional)

Grouts come in a wide range of colors, but if you can’t find a pre-colored grout you like, you can add colorant during the mixing process. Thoroughly mix the grout and colorant so there aren’t any clumps or variations in color. 

6. Apply the Grout

Using a grout float, sweep the grout across the tiles and joints. Gently press the grout into the joints. 

7. Remove Excess Grout

Use a nylon sponge to remove excess grout from the tile surface. You may need to rinse the sponge to prevent spreading rather than removing excess grout.

8. Let the Grout Dry and Cure

The grout may dry within a few hours, but it also needs to cure, which can take a few days. Check the manufacturer’s instructions to know how long the grout needs to cure. Do not use the tiled area until the grout cures.

9. Seal the Grout (Optional)

If the grout doesn’t already have sealant in it, apply a sealant to prevent stain and moisture penetration. Sealants can change the color of the grout, typically making it darker and shinier. Allow the sealant to dry according to the manufacturer's instructions before using the tiled area.

How to Prevent Grout From Discoloring

Grout can discolor for many reasons, especially lighter-colored grout. Common causes of discoloration include:

• Cleaning products with bleach

• Dirty sponges or cleaning cloths

• Minerals in your water 

• Personal care products (shampoos, soaps, conditioners, etc.) that come in contact with the grout

To keep your tile job looking its best, it’s worth learning how to clean grout properly. You can also schedule regular cleanings with nearby grout and tile cleaners.

Bleach can discolor grout, so it’s preferable to use cleaning products that don’t contain it. You can gently clean grout without staining it by using white vinegar along with a paste made of water and baking soda.

Make sure your cleaning supplies are free of grease or debris that could potentially transfer to the grout’s surface. Rinsing the tiles after you shower will also help keep grout from discoloring. 

Finally, be sure to seal the grout regularly. Sealants prevent substances from penetrating the grout’s pores. You can use mix-in sealants when mixing the grout yourself, apply a secondary sealant after the grout cures, or use a grout that already contains a sealant.

DIY vs. Hiring a Pro

Repainting your grout is definitely a DIY project you can do yourself. Grout colorants cost less than $25, and grout colorant pens cost under $10. Most pros won’t come out for a grout recoloring job simply because it doesn’t require enough billable hours to make it worth their time. 

Removing and replacing grout is another doable DIY project, but there are more tools and time involved. There’s also more room for error. The new grout and sealant will probably cost less than $40, but there’s the potential for issues like cracking the tile or damaging the substrate. If you’d rather leave this task to the pros, tile installation costs $3 to $15 per square foot, with labor running from $30 to $120 per hour.