Should You Use Sanded Or Unsanded Grout? A Comparison

When installing tile, one of the most important decisions is choosing between sanded or unsanded grout. Grout fills the joints between tiles, and its texture and durability have a major impact on the look and longevity of your tiling project. unsanded grout to help you make the optimal choice.

We'll compare the composition, applications, finishing properties, installation techniques, and pros and cons of each type. We'll also provide tips on how to pick the right grout for your specific tile size, location, and traffic level. Let's take a comprehensive look at these two versatile grouting options.

Defining Sanded and Unsanded Grout

First, it helps to understand exactly what sanded and unsanded grouts are:

• Sanded grout contains fine silica sand particles that allow it to fill wider joints between tiles. The sand comprises between 35-45% of the total volume, giving sanded grout greater durability and resistance to cracking and shrinkage as it cures.

• Unsanded grout is a smooth mixture without sand particles, making it suitable for filling narrower grout lines. The lack of sand allows unsanded grout to completely fill hairline joints.

Material Composition

While both types contain Portland cement, hydrated lime, and pigments, their differing sand content leads to variations in texture and performance. Sanded grout's mortar-like consistency comes from the addition of finely graded sand. Unsanded grout achieves a smoother, glue-like texture without sand particles. This allows it to fully penetrate thin gaps between tiles.

Finishing Properties

When cured, unsanded grout provides a uniform, seamless appearance, while sanded grout has a slightly grittier finish. The sand granules in sanded grout are approximately the size of a grain of superfine sugar. This gives the joint surface more texture.

The smoothness of unsanded grout prevents it from scratching or damaging polished and delicate tile materials during application. However, the lack of aggregate also makes unsanded grout more prone to shrinkage cracking over time, especially on floors. The sand in sanded grout improves its compressive strength and resistance to cracking under stress.

Joint Width Guidelines

The key factor in choosing between the two grout types is the width of the joints being filled. Industry standards recommend:

• Sanded grout for tile joints 1/8 inch and wider
• Unsanded grout for narrow grout lines less than 1/8 inch
• Either type may work for medium joint widths in the 1/16 to 1/8 inch range

The sand particles in sanded grout allow it to pack into wider grout gaps and develop durability. Unsanded grout is formulated to spread easily into hairline spaces.

When to Use Sanded vs. Unsanded Grout

Given their different properties and ideal joint widths, here are the best applications for each grout type:

Sanded Grout Works Well For:

• Floor tile with joints 1/8 inch and wider
• Stone flooring like granite, slate, or limestone
• Outdoor tile projects prone to freezing
• Showers, countertops, and backsplashes with larger tile
• Any installation requiring maximum strength and longevity

Sanded grout resists cracking, weathering, and heavy foot traffic, making it ideal for flooring and outdoor areas. The coarse texture also creates traction to prevent slipping on floor tile when wet.

Unsanded Grout is Best For:

• Wall tiles with thin grout lines under 1/8 inch
• Glass, marble, or other delicate tile surfaces
• Showers and tub surrounds with small mosaic tiles
• Minimizing visible joints in subway tiles or brick patterns
• Creating a smooth finished appearance

The fine texture prevents unsanded grout from scratching glass tile or polished stone. It can fully penetrate tight joints between small mosaic tiles.

Matching Grout to Tile Size

As a guideline for selecting grout:

• Use sanded grout for tile sizes larger than 4x4 inches
• Use unsanded grout for mosaic tiles smaller than 2x2 inches
• For sizes in between, the grout choice depends on joint width

Larger format tiles require wider joints that benefit from sanded grout's durability. Small mosaics have narrow grout lines suitable for unsanded grout.

How to Apply Sanded and Unsanded Grout

While the overall process is similar, there are some technique differences to get great results with each grout type:

Step 1: Prepare the Tile Surface

Proper prep before grouting is crucial:

• Allow tile mortar to fully cure for 24-48 hours
• Confirm joints are clean, uniform depth, and squarely spaced
• Remove any spacers, debris, or excess mortar
• Apply grout release to polished or easily stained surfaces

This provides an optimally clean surface for the grout to adhere and fill joints.

Step 2: Mix the Grout

Follow package instructions carefully when mixing:

• Sanded grout uses less water for a thick, mortar-like consistency
• Unsanded grout requires more water to become smooth and fluid
• Avoid over-mixing, which can vary color and performance

Only mix what you can apply within 30-45 minutes before the grout hardens. Have all your tools ready before mixing.

Step 3: Apply the Grout

Work the grout into joints using a rubber float held at a 45deg angle:

• Force sanded grout vigorously into each joint to compact
• Apply unsanded grout gently to avoid dragging it from thin spaces
• Move float diagonally across tiles to fill evenly

Sanded grout requires muscle to fully occupy wider joints. Unsanded grout should just skim the tile surface to stay in narrow grout lines.

Step 4: Clean Up and Finish

Proper cleanup and curing affect the final cured appearance:

• Use minimal water when cleaning sanded grout haze
• More water is fine with unsanded to ensure complete joint filling
• Finish unsanded grout with a damp cheesecloth versus a wet sponge

Once any low spots are smoothed, allow the grout to cure fully for 72 hours before heavy use. Sanded grout takes longer to cure and harden completely.