Sanded vs Unsanded
vs Epoxy Grout
Choosing the wrong grout type causes cracking, scratching, or packing failure. The decision is driven by joint width first, then tile sensitivity and wet-area requirements. Use the grout calculator to estimate quantity once you've selected the right type for your project.
Calculate Grout Quantity
Enter tile size, joint width and area — get exact grout quantity in bags for sanded, unsanded, or epoxy.
Full Grout Comparison
Always follow the product manufacturer's instructions over general guidance — epoxy brands in particular have specific mixing ratios and open times that vary by product.
| Property | Sanded | Unsanded | Epoxy |
|---|---|---|---|
| Joint Width | 1/8" (3mm) and wider | Under 1/8" (3mm) | Any width |
| Composition | Portland cement + sand + pigment | Portland cement + fine filler | Resin + hardener (two-part) |
| Best Surface | Floors, outdoor, wide wall joints | Wall tile, backsplash, glass, polished stone | Commercial, pools, kitchens, wet areas |
| Water Resistance | Moderate (sealing recommended) | Moderate (sealing recommended) | Excellent (fully stain and chemical resistant) |
| Tile Sensitivity | May scratch polished or soft stone | Safe on all surfaces | Safe on all surfaces |
| Handling Difficulty | Easy | Easy | Difficult — fast cure time, precise mixing |
| Relative Cost | Low | Low–Medium | High |
Grout Type by Room and Project
Kitchen Backsplash
Unsanded or epoxy
Narrow joints (1/16"–1/8") and grease resistance; epoxy if you cook heavily
Bathroom Floor
Sanded
Wide joints (3/16"+) with floor tile are standard; seal after curing
Shower Walls
Unsanded or epoxy
Narrow joints prevent scratching; epoxy eliminates mold staining in wet areas
Shower Floor (mosaic)
Unsanded
Mosaic grids use 1/16"–1/8" joints that require unsanded formulas
Swimming Pool
Epoxy only
Chemical exposure, constant water contact, and cleaning agents demand fully non-porous epoxy
Polished Stone or Glass
Unsanded
Sand particles in sanded grout will permanently scratch polished surfaces during wiping
Always read and follow the product manufacturer's technical data sheet. Epoxy grout in particular has variable open times, specific temperature requirements, and mixing ratios that differ between brands. General guidance here does not substitute product instructions.
Marcus Sterling
Certified Master Tile Installer & Technical Estimator
This guide has been technically reviewed and approved by Marcus Sterling. Marcus has over 20 years of hands-on experience in residential and commercial tile setting. He is a certified installer specializing in moisture diagnostics, deflection analysis, complex layouts, and estimation accuracy.
Grout Type FAQs
Common questions about choosing between sanded, unsanded, and epoxy grout.
When should I use sanded grout?▼
Use sanded grout for joints 1/8" (3mm) wide and wider. Sanded grout contains coarse sand particles that give body and prevent shrinkage in wider gaps. It's the standard choice for floor tile, outdoor tile, and any wall tile with joints wider than 1/8".
When should I use unsanded grout?▼
Use unsanded grout for joints narrower than 1/8" (3mm). The fine formula packs properly into narrow joints where sand particles are too large. Unsanded grout is also the correct choice for polished stone or glass tile that can be scratched by sand.
Is epoxy grout worth it?▼
Epoxy grout is fully stain-proof and chemically resistant — it does not require sealing and won't absorb oil, wine, or cleaning chemicals. It's worth the extra cost in kitchens, commercial areas, pools, and showers. It's significantly harder to apply due to rapid cure time and requires precise mixing.
Can I use sanded grout on polished marble or glass?▼
No. Sanded grout contains coarse particles that will permanently scratch polished marble, travertine, and glass tile during the grouting process. Use unsanded grout for all polished stone and glass surfaces.
Do I need to seal sanded or unsanded grout?▼
Yes — both cement-based sanded and unsanded grouts are porous and should be sealed 72 hours after installation and again every 1–2 years. Epoxy grout is non-porous and does not require sealing.