Sanded vs. Unsanded Tile Grout: Guide, Pros & Cons

Sanded vs. Unsanded Grout: A Contractor's Guide to Choosing the Right Once

The Bottom Line:

Sanded grout contains sand particles that make it stronger and more durable for wide joints (1/8 inch and larger) and high-traffic floors, while unsanded grout is a smooth, sand-free formula designed for narrow joints (under 1/8 inch) and delicate tiles that could be scratched by sand, and choosing the wrong one leads to cracked grout, scratched tile surfaces, or premature failure of the installation.

Quick Summary (For Contractors Who Have Seen Grout Fail)

You have been there. You grout a beautiful marble backsplash with sanded grout. The next day, you see fine scratches all over the polished surface. The customer is furious. Or you grout a bathroom floor with unsanded grout because you had some left over. Six months later, the grout is cracking and crumbling out of the joints. The customer calls you back.

Here is the truth. Grout selection is not a guessing game. The TCNA standards are clear. Joints 1/8 inch and larger require sanded grout. Joints under 1/8 inch require unsanded grout. At exactly 1/8 inch, you have a choice, but you must consider the tile type and the installation location.

Sanded grout is stronger, more durable, and resists cracking. Unsanded grout is smoother, less abrasive, and safer for delicate surfaces. Choose wrong, and you will be back to fix it.

This guide is for contractors who want to understand exactly when to use each type, the pros and cons of both, and how to avoid the most common grout mistakes.

Let us get to work.

What Is Sanded Grout?

Sanded grout is a cement-based grout that contains fine sand particles mixed into the formula. The sand acts as a filler and a strengthening agent. It gives the grout body, reduces shrinkage as it dries, and makes it more resistant to cracking under pressure.

The composition. Sanded grout is made from Portland cement, fine sand, and additives that improve workability and bond strength. The sand particles are typically graded to specific sizes depending on the manufacturer's formula.

The texture. Sanded grout has a gritty, rough texture. You can feel the sand when you run your fingers through it. This texture is what gives it its strength, but it is also what can scratch delicate tile surfaces.

The joint size. Sanded grout is designed for grout joints that are 1/8 inch (3 mm) or larger. For joints smaller than that, the sand particles cannot fit properly into the narrow space. The grout will not pack tightly, and it will not cure correctly.

The durability. Sanded grout is the stronger of the two standard grout types. The sand particles interlock and create a dense, rigid structure that resists compression and movement. It is the standard choice for floor tile installations and any area that bears weight or experiences heavy foot traffic.

What Is Unsanded Grout?

Unsanded grout is a cement-based grout that contains no sand particles. It relies on polymers and other additives for strength and adhesion. The absence of sand gives it a smooth, creamy texture that is easy to work with, especially in tight spaces.

The composition. Unsanded grout is made from Portland cement, fine fillers (but not sand), and polymer additives that improve flexibility and bond strength. The polymers also make it more water-resistant than traditional sanded grout.

The texture. Unsanded grout is smooth and creamy. It feels like thick paste or heavy cream. This smooth texture allows it to flow easily into narrow joints without leaving voids or air pockets.

The joint size. Unsanded grout is designed for grout joints that are 1/8 inch (3 mm) or smaller. The smooth formula can fill even the tightest 1/16 inch joints without difficulty.

The adhesion. Unsanded grout is stickier than sanded grout. This makes it ideal for vertical applications like walls and backsplashes because it adheres better to upright surfaces and does not sag or slide out of the joint before it cures.

The TCNA Standard: The 1/8 Inch Rule

The Tile Council of North America (TCNA) has a clear rule for grout selection. For grout joints 1/8 inch and over, use sanded grout. For grout joints 1/8 inch and under, use unsanded grout.

Why 1/8 inch? The reason is simple. Sand particles need room to fit between the tiles. In a joint smaller than 1/8 inch, the sand cannot pack properly. The grout will be loose, weak, and prone to cracking. In a joint larger than 1/8 inch, unsanded grout shrinks too much as it dries. The shrinkage creates cracks and voids that lead to failure.

The overlap zone. At exactly 1/8 inch, both types can work. This is the overlap zone where you have a choice. However, you must consider the tile type, the location, and the traffic level before making your decision.

The absolute minimum. TCNA states that in no circumstance shall the grout joint be less than 1/16 inch. For joints that small, unsanded grout is the only option.

Sanded Grout: Pros and Cons

Pros

Superior strength and durability. The sand particles in sanded grout create a dense, interlocking structure that resists cracking and compression. Sanded grout withstands pressure better than unsanded grout, making it the best choice for floors and any tile that bears weight.

Less shrinkage. Sanded grout shrinks less as it dries because the sand particles take up space that would otherwise be occupied by cement and water. Less shrinkage means fewer cracks and a longer-lasting installation.

Better for wide joints. Sanded grout is designed for joints 1/8 inch and larger. The sand fills the space completely and creates a dense, solid grout line that will not crack or crumble under pressure.

More economical. Sand is a cheap filler. Sanded grout costs less than unsanded grout because the sand replaces more expensive polymers and additives.

Resists cracking under pressure. Sanded grout is more rigid and less likely to crack when subjected to foot traffic, furniture, or other loads. This makes it the standard choice for most interior flooring installations.

Cons

Can scratch delicate tiles. The sand particles in sanded grout are abrasive. They can scratch polished stone, glass, metal, glazed ceramic, and other delicate surfaces. Avoid sanded grout on marble, glass tile, polished porcelain, and metallic finishes.

Rougher texture. Sanded grout has a gritty, rough finish. Some customers prefer the smooth, sleek look of unsanded grout, especially on walls and backsplashes.

Harder to clean in tight joints. The sand particles can make it difficult to pack the grout into very narrow joints. The sand can also make it harder to clean excess grout from the tile surface without scratching.

Not suitable for joints under 1/8 inch. The sand particles simply cannot fit into joints smaller than 1/8 inch. The grout will be loose, weak, and prone to failure.

Unsanded Grout: Pros and Cons

Pros

Safe for delicate tiles. Unsanded grout has no sand, so it will not scratch polished stone, glass, metal, or glazed ceramic surfaces. It is the only safe choice for delicate and easily scratched tile.

Smooth, sleek finish. Unsanded grout has a smooth, creamy texture that creates a clean, modern look. The smooth finish is especially popular on walls and backsplashes.

Easier to apply in tight joints. The smooth, sand-free formula flows easily into narrow joints. It fills every void without leaving air pockets or gaps. This makes it ideal for 1/16 inch and 1/8 inch joints.

Better adhesion on vertical surfaces. Unsanded grout is stickier than sanded grout. It adheres better to walls and other vertical surfaces without sagging or sliding out of the joint before it cures.

Ideal for narrow joints. Unsanded grout is specifically designed for joints under 1/8 inch. It does not shrink excessively in narrow spaces, and it cures to a dense, solid finish.

Cons

Less durable. Unsanded grout is weaker than sanded grout. It is more prone to cracking under pressure, making it unsuitable for most flooring applications.

More prone to cracking. The absence of sand means unsanded grout shrinks more as it dries. The shrinkage creates stress that can lead to cracks, especially in wider joints.

More expensive. Unsanded grout relies on expensive polymers for strength instead of cheap sand filler. This makes it more costly than sanded grout.

Not suitable for joints over 1/8 inch. Unsanded grout shrinks too much in wider joints. The shrinkage creates cracks and voids that lead to failure. It is not recommended for joints larger than 1/8 inch.

Longer drying time. Unsanded grout can take up to 72 hours to dry completely. This can slow down your installation schedule.

Grout Selection Decision Matrix

Grout Selection by Tile Type

Here is how to choose based on what you are installing.

Ceramic Tile

For standard ceramic tile, sanded grout is usually the best choice for floors. It provides the strength and durability needed for foot traffic. For walls and backsplashes, unsanded grout works well, especially with tight joints under 1/8 inch.

When to use unsanded. If your ceramic tile is highly glazed or polished, use unsanded grout to avoid scratching the surface.

Porcelain Tile

Porcelain is denser than ceramic and often has a polished or matte finish. For floor installations, sanded grout is recommended for joints 1/8 inch and larger. For wall installations with tight joints, unsanded grout is a good choice.

When to use unsanded. Polished porcelain can scratch easily. Use unsanded grout on polished porcelain tiles to protect the finish.

Natural Stone

Marble, travertine, limestone, slate, and granite are all natural stone. They vary in hardness and porosity.

Marble and polished stone. Always use unsanded grout. The sand in sanded grout will scratch the polished surface. Epoxy grout is also an excellent choice for marble.

Travertine and limestone. These are softer stones. Unsanded grout is recommended to avoid scratching.

Slate and granite. These are harder stones. Sanded grout can be used on slate and granite, but always test a small area first. For narrow joints, unsanded grout is still the safer choice.

Glass Tile

Glass tile is delicate and easily scratched. Always use unsanded grout on glass tile. Never use sanded grout. The sand will scratch the glass surface permanently.

Metal Tile

Metal tiles have delicate finishes that can scratch. Use unsanded grout on metal tile to protect the surface.

Mosaic Tile

Mosaic tiles often have tight joints under 1/8 inch. Unsanded grout is the standard choice. However, some ceramic mosaics with wider joints (1/8 inch or more) can use sanded grout.

Grout Selection by Location

Floors

Floors bear weight and experience foot traffic. Sanded grout is almost always the right choice for floor tile installations. It is stronger, more durable, and resists cracking under pressure. For polished stone floors, unsanded grout is still required to prevent scratching.

Walls

Walls do not bear weight. Unsanded grout is often the preferred choice for walls because it is stickier and adheres better to vertical surfaces. It also provides a smooth, sleek finish that looks great on backsplashes and shower walls.

Showers and Wet Areas

Showers and wet areas need grout that resists water and mold. Both sanded and unsanded grout can work, but you must seal them properly. Epoxy grout is the best choice for showers because it is waterproof and stain-proof. If you are using cement-based grout in a shower, always seal it after curing.

High-Traffic Commercial Areas

Retail stores, restaurants, and office lobbies need the strongest grout possible. Sanded grout is the standard choice for commercial floors. For areas with heavy equipment or rolling loads, consider epoxy grout for maximum durability.

Common Grout Mistakes That Cost Contractors Money

I see these mistakes on job sites constantly.

Mistake 1: Using sanded grout on polished marble. The sand scratches the surface. The customer notices. You have to replace the tile or polish out the scratches. Always use unsanded grout on polished stone.

Mistake 2: Using unsanded grout on wide joints. You use unsanded grout in a 1/4 inch joint. The grout shrinks. It cracks. It crumbles. The customer calls you back. Always use sanded grout on joints 1/8 inch and larger.

Mistake 3: Using unsanded grout on a floor. Unsanded grout is not strong enough for floors. It cracks under foot traffic. The grout fails. You are back to fix it. Always use sanded grout on floor tiles.

Mistake 4: Not sealing grout in wet areas. You use cement-based grout in a shower. You do not seal it. Water soaks in. Mold grows. The grout deteriorates. The customer calls you back. Always seal cement-based grout in wet areas.

Mistake 5: Using the wrong grout on glass tile. You use sanded grout on glass tile. The sand scratches the glass. The tile is ruined. You have to replace it. Always use unsanded grout on glass tile.

Mistake 6: Not matching grout color across batches. You buy multiple bags of grout. They are from different batches. The colors do not match. The grout lines look patchy. The customer is unhappy. Always buy enough grout from the same batch to complete the job.

Mistake 7: Grouting movement joints. You fill the perimeter gap or change-of-plane joint with grout. The floor expands. The grout cracks. The floor buckles. Always use flexible sealant in movement joints, not grout.

Quick Reference Table: Grout Selection by Joint Size and Tile Type

Frequently Asked Questions

What is the difference between sanded and unsanded grout?

Sanded grout contains sand particles that make it stronger and more durable. Unsanded grout has no sand and is smoother and safer for delicate tiles.

When should I use sanded grout?

Use sanded grout for grout joints 1/8 inch (3 mm) and larger, for floor tile installations, and for high-traffic areas.

When should I use unsanded grout?

Use unsanded grout for grout joints under 1/8 inch, for wall tile and backsplash installations, and for delicate tiles like glass, polished marble, and metal.

Can I use sanded grout on glass tile?

No. The sand in sanded grout will scratch glass tile permanently. Always use unsanded grout on glass tile.

Can I use unsanded grout on a floor?

Not recommended. Unsanded grout is not strong enough for floor tile installations. It cracks under foot traffic and pressure. Use sanded grout on floors.

What joint size determines which grout to use?

The TCNA standard is clear. Joints 1/8 inch and larger require sanded grout. Joints under 1/8 inch require unsanded grout.

Is epoxy grout better than sanded or unsanded grout?

Epoxy grout is more durable, stain-proof, and waterproof than cement-based grout. It is also more expensive and harder to apply. It is the best choice for showers, pools, and high-traffic commercial areas.

Do I need to seal unsanded grout?

Yes. Cement-based unsanded grout is porous and needs to be sealed, especially in wet areas. Epoxy grout does not need sealing.

How long does grout take to dry?

Sanded grout typically dries in 24 to 48 hours. Unsanded grout can take up to 72 hours to dry completely. Always check the manufacturer's instructions.

Can I use sanded grout on polished marble?

No. The sand will scratch the polished surface. Always use unsanded grout on polished marble and other polished stone.

A Final Word From The Tile Shoppe

Here is the honest truth. Grout selection is not complicated, but it is unforgiving. Choose wrong, and you will be back to fix it. The sand in sanded grout gives it strength, but it also scratches delicate surfaces. The smoothness of unsanded grout protects fragile tiles, but it lacks the strength for floors and wide joints.

The TCNA standard is your guide. Joints 1/8 inch and larger need sanded grout. Joints under 1/8 inch need unsanded grout. At exactly 1/8 inch, you have a choice, but consider the tile type and location before you decide.

At The Tile Shoppe, we carry both sanded and unsanded grout in a wide range of colors. We also carry epoxy grout for the most demanding applications. Come talk to us before your next job. We will help you choose the right grout for your tile, your joint size, and your installation location.

Because a floor with cracked grout is a floor that makes you look bad. A floor with scratched tiles is a floor that costs you money. Choose right the first time, and you will never have to go back.

Now go grout some tile. And pick the right one.