Polyblend Grout Renew, made by Custom Building Products, is a colorant and sealer that restores the look of tired, stained, or mismatched grout without the mess of tearing it out. Instead of regrouting an entire floor or backsplash, you brush this product over the existing grout lines to recolor and seal them in one step. For homeowners battling discolored grout, it is one of the most cost-effective upgrades you can make in a kitchen or bathroom.
Part of our Tile & Grout guide — explore the full guide →
This guide explains what Grout Renew does, where it works best, how to apply it for clean results, and how to keep your refreshed grout looking good for years.
What Polyblend Grout Renew Does
Grout Renew is designed to coat existing, cured cement-based grout joints with a uniform, fresh color while sealing them against moisture and stains. Over time grout fades, picks up dirt, and develops uneven patches that no amount of scrubbing fully removes. Rather than living with discoloration or undertaking a full regrout, you can change or refresh the color and lock out future staining in a single application.
Because it both colors and seals, the product serves a dual purpose. The renewed surface resists dirt and mildew better than bare grout, which means your lines stay cleaner-looking with less effort going forward. It is a finishing treatment, not a structural repair, so it works on grout that is sound, not crumbling.
Where It Works Best
This colorant is intended for cured cement-based sanded and unsanded grout joints on floors, walls, and backsplashes. It shines anywhere grout has faded or stained unevenly but the joints themselves are still intact.
- Kitchen and bathroom backsplashes where grout has darkened from grease and grime.
- Tile floors with traffic-worn, blotchy grout lines.
- Bathroom walls and tub surrounds where grout looks dingy despite cleaning.
- Projects where you want to change the grout color to match a new design without retiling.
It is not a fix for grout that is cracked, missing, or powdery. If joints are deteriorating, repair or replace them first, then apply the colorant once the new grout has cured. Always check the manufacturer’s directions for suitability on your specific tile and grout type, and avoid using colorant on epoxy grout or polished natural stone unless the product label confirms it is appropriate.
Tools and Materials You Will Need
Gathering everything before you start keeps the job smooth and prevents the colorant from drying unevenly while you hunt for supplies.
- Polyblend Grout Renew in your chosen color.
- A small stiff-bristle grout brush or a dedicated applicator brush.
- Clean rags or paper towels and a sponge.
- A bucket of clean water.
- Knee pads for floor work and gloves to keep your hands clean.
- Painter’s tape if you want to protect adjacent surfaces.
A toothbrush or fine detail brush helps with tight corners and narrow joints. Keep a damp rag within reach at all times, because wiping excess colorant off the tile promptly is the secret to a clean finish.
Step-by-Step Application
Preparation drives the result more than anything else. Colorant will not adhere properly to dirty or sealed grout, so cleaning comes first.
- Clean the grout thoroughly to remove dirt, grease, soap scum, and any old sealer, then let it dry completely.
- Shake the bottle well so the color is evenly mixed.
- Dip the brush and work the colorant into the grout joint, covering the full width of the line.
- Work in small sections so you can wipe before the product dries on the tile face.
- Within the time stated on the label, wipe excess off the tile surface with a clean, damp rag, leaving color only in the joints.
- Buff away any haze with a dry cloth and inspect for missed spots, touching up as needed.
Patience pays off. Rushing leaves smears on the tile, while moving in manageable sections keeps the lines crisp and the surrounding tile clean.
Drying, Curing, and Aftercare
Allow the renewed grout to dry and cure according to the directions on the container before exposing it to water or heavy traffic. Drying to the touch happens fairly quickly, but full cure, especially before a shower returns to use, takes longer, often a day or more. Resist the urge to test it early.
Once cured, the colored, sealed surface is easy to maintain. Clean with a mild, pH-neutral cleaner and avoid harsh acidic or abrasive products that can wear down the finish over time. Because the colorant seals the joint, routine cleaning becomes simpler and stains are far less likely to take hold.
Safety and Common Mistakes
Work in a ventilated area and wear gloves to keep the colorant off your skin, following all precautions on the product label. Keep the room aired out while you work and during drying. If you have sensitivities, eye protection adds a margin of safety when working overhead on walls.
The most common mistakes are easy to avoid. Skipping the cleaning step leaves colorant that peels later. Letting the product dry on the tile before wiping creates stubborn haze. Applying it to crumbling grout wastes effort, because the joint needs to be sound. Rushing the cure time can mar the finish. Test the color in an inconspicuous spot first so you are happy with the shade before committing to the whole room.
How Long the Results Last
With proper preparation and application, renewed grout can keep its fresh color for several years before it needs attention. The sealing action helps the joints resist the dirt and grease that cause discoloration in the first place, so the surface stays looking clean far longer than untreated grout. Longevity depends on the traffic and moisture the area sees, with shower floors and busy kitchen backsplashes wearing faster than a guest bathroom wall.
When the color eventually dulls in high-use spots, you can usually touch up those areas rather than redoing the whole room. Clean the worn section, let it dry, and reapply the colorant just as you did originally. This spot-treatment ability is part of what makes the product so practical, since maintenance is quick and inexpensive compared with regrouting.
Is Grout Renew Worth It?
For grout that is intact but discolored, Polyblend Grout Renew is a low-cost, high-impact upgrade. It transforms the appearance of a backsplash, floor, or shower in an afternoon, seals the joints against future grime, and spares you the dust, time, and expense of regrouting. As long as your grout is structurally sound and you prep carefully, it delivers a fresh, uniform look that makes the whole tiled surface feel new again.
