How to Clean Unsanded Grout Without Damaging It
Unsanded grout is common in narrow tile joints, especially on walls, shower surrounds, and polished tile installations.
Knowing how to clean unsanded grout matters because the wrong brush, cleaner, or scrubbing method can etch the grout surface, loosen pigments, or widen the joint.
The good news is that unsanded grout is usually easy to maintain when you use the right tools and a careful cleaning routine.
With a few household ingredients and the correct technique, you can remove soap scum, mildew, and everyday buildup while keeping grout lines intact.
What Is Unsanded Grout?
Unsanded grout is a cement-based grout made without sand particles.
It is designed for narrow joints, typically less than 1/8 inch wide, where sanded grout could scratch delicate tile surfaces or not fit smoothly into the joint.
Because it has a smoother texture, unsanded grout is often used with ceramic tile, glass tile, marble, and other polished surfaces.
It is more prone to shrinkage and cracking in wider joints, but when installed correctly it creates a clean finish that blends well with modern tilework.
Why Unsanded Grout Gets Dirty
Grout is porous, so it absorbs moisture, soap residue, body oils, and airborne dirt over time.
In kitchens, grease and food splatter can discolor grout lines.
In bathrooms, humidity encourages mildew and soap scum to cling to the surface.
Common causes of stained grout include:
- Hard water deposits
- Soap scum buildup
- Mold and mildew growth
- Grease and cooking residue
- Track-in dirt from shoes
- Unsealed or worn grout
Best Tools for Cleaning Unsanded Grout
The safest cleaning method starts with the right tools.
Unsanded grout can be damaged by abrasive pads, wire brushes, and overly stiff bristles, so choose gentle materials that lift dirt without wearing down the surface.
- Soft-bristle grout brush or old toothbrush
- Microfiber cloths or soft sponges
- Spray bottle
- Bucket of warm water
- pH-neutral tile cleaner or mild dish soap
- Baking soda
- Hydrogen peroxide for stain removal
- Rubber gloves
How to Clean Unsanded Grout Step by Step
If you want to clean unsanded grout effectively, start with the gentlest option and escalate only if needed.
This reduces the risk of surface wear and keeps the grout color more consistent.
1. Remove loose dirt first
Vacuum the area or sweep thoroughly before applying any liquid cleaner.
Dry debris can scratch grout and tile when rubbed into the surface.
2. Apply a mild cleaning solution
Mix warm water with a few drops of mild dish soap, or use a pH-neutral tile cleaner.
Spray or apply the solution directly to the grout lines and let it sit for 5 to 10 minutes to loosen grime.
3. Scrub gently with a soft brush
Use small circular motions or short back-and-forth strokes with light pressure.
Focus on one section at a time so the cleaner does not dry before you scrub.
4. Rinse with clean water
Wipe away loosened soil with a damp microfiber cloth or sponge.
Rinse the area well to prevent residue from attracting more dirt.
5. Dry the surface completely
Use a dry towel to remove moisture from the tile and grout.
Drying helps prevent mildew and water spots, especially in showers and bathrooms.
How to Clean Stained Unsanded Grout
For deeper discoloration, a targeted stain remover can help.
Always test any solution in an inconspicuous area first, especially on colored grout or natural stone tile.
Baking soda paste
Make a paste using baking soda and water, then apply it to the grout lines.
Let it rest for 5 to 10 minutes and scrub gently with a soft brush before rinsing.
This method works well for light staining and deodorizing.
Hydrogen peroxide
Hydrogen peroxide can help with organic stains and mildew marks.
Apply it to the grout, allow it to sit briefly, then scrub and rinse.
Use it carefully on colored grout because repeated use may lighten the pigment.
Commercial grout cleaner
If household methods are not enough, choose a cleaner labeled safe for unsanded grout and compatible with your tile material.
Avoid products that contain harsh acids unless the label specifically says they are safe for your surface.
What Not to Use on Unsanded Grout
Some cleaning products and tools can make grout look worse or cause permanent damage.
If your goal is to clean unsanded grout safely, avoid anything overly abrasive or chemically harsh.
- Steel wool or wire brushes
- Magic erasers used with heavy pressure
- Bleach on colored grout
- Acidic cleaners on natural stone, marble, or limestone
- Steam cleaning on delicate or poorly installed grout
- Excessive scrubbing that removes the grout surface
Bleach may temporarily whiten stained grout, but repeated use can break down grout and affect color.
Acidic cleaners can damage both grout and adjacent tile, especially in stone installations.
How to Clean Unsanded Grout in a Shower
Shower grout is exposed to constant moisture, so soap scum and mildew are common.
Start by spraying the area with a mild cleaner and letting it sit, then scrub lightly and rinse thoroughly.
To reduce future buildup, improve ventilation by running an exhaust fan, opening a window, or wiping down shower walls after use.
Keeping the shower dry between cleanings is one of the most effective ways to preserve grout appearance.
How to Clean Unsanded Grout on Floors
Floor grout often holds more dirt because it collects foot traffic and tracked-in debris.
Vacuum or sweep first, then clean in small sections to prevent dirty water from spreading.
For kitchen floors, a degreasing dish soap solution can help break down oily residue.
For entryways or high-traffic areas, a second rinse may be needed to remove all cleaner and lifted soil.
How to Keep Unsanded Grout Clean Longer
Routine maintenance is easier than repeated deep cleaning.
A few simple habits can protect grout lines and reduce the chance of staining.
- Wipe spills quickly before they soak in
- Use doormats to reduce tracked dirt
- Dry shower walls after use
- Clean tile regularly with a pH-neutral cleaner
- Reseal grout when recommended by the manufacturer
- Improve ventilation in bathrooms and kitchens
Sealing is especially important for cement-based grout because it slows moisture absorption and makes routine cleaning more effective.
Check the product label or ask the installer whether your grout is already sealed.
When to Call a Professional
If grout remains dark after cleaning, has deep mildew staining, or is cracking and crumbling, a professional tile cleaner or restoration specialist may be the best option.
Persistent stains can also signal a moisture problem behind the tile, especially in showers or around sinks.
Professionals can assess whether the grout needs deep cleaning, color sealing, or replacement.
That can save time and prevent further damage when the grout is already worn or compromised.
Quick Grout Cleaning Checklist
- Remove dust and debris first
- Use a mild or pH-neutral cleaner
- Scrub with a soft brush only
- Rinse thoroughly after cleaning
- Dry the area to prevent mildew
- Avoid harsh abrasives and acids
With the right approach, learning how to clean unsanded grout becomes a simple part of tile care rather than a risky chore.
Gentle tools, consistent maintenance, and careful product choices will keep grout lines looking clean while protecting the tile around them.