1/8 vs 1/16 Grout Line Wood Look Tile: Which Is Right?

Choosing between a 1/8 vs 1/16 grout line wood look tile installation is one of the biggest decisions for getting that convincing hardwood appearance from porcelain planks. The grout joint is the giveaway that separates realistic wood-look tile from an obvious tile floor, so narrower is generally better looking, but there are real practical limits tied to tile warpage, lippage, and industry standards. This guide explains what each spacing looks like, why you cannot always go as tight as you want, and how to pick the joint width that balances realism with a flat, durable, and code-compliant floor.

Part of our Tile & Grout guide — explore the full guide →

Why Grout Line Width Matters for Wood Look

Real hardwood boards butt together with almost no visible gap. To mimic that, tile installers want the tightest practical grout joint. A wide, obvious grout line breaks the wood illusion and reminds the eye it is looking at tile. That is why homeowners installing wood-look plank tile gravitate toward the smallest joints possible, typically 1/16 inch or 1/8 inch. But the plank format introduces challenges, especially warpage along the length, that prevent joints from going as tight as ceramic subway tile.

What a 1/16 Inch Grout Line Looks Like

A 1/16 inch (about 1.6 mm) joint is the tightest most installers will attempt on wood-look tile. Its advantages:

• Delivers the most convincing hardwood appearance with a barely-there seam.
• Minimizes the visual grid, so the floor reads as continuous planks.
• Works best with rectified tile (precision-cut, perfectly straight edges).

The catch is that very tight joints leave almost no room to adjust for tile size variation and warpage. On long planks, any bowing along the length gets amplified when joints are this small, making lippage (uneven edges you can feel with your foot) much harder to control.

What a 1/8 Inch Grout Line Looks Like

A 1/8 inch (about 3 mm) joint is the most commonly recommended spacing for wood-look plank tile. Its advantages:

• Gives enough room to absorb the natural warpage and size variation of long planks.
• Makes it far easier to keep the floor flat and lippage-free.
• Still looks slim and wood-like, especially with a matching grout color.
• Is the width many tile manufacturers specifically recommend in their instructions.

While slightly more visible than 1/16 inch, a 1/8 inch joint in a well-matched grout color still produces a beautiful, realistic wood floor and is much more forgiving to install.

The Industry Standard You Should Know

There is a real rule behind this debate. The Tile Council of North America (TCNA) recommends that the grout joint be at least three times the variation in the tile facial dimension, and for pressed floor tile the general guidance is a minimum joint of about 1/8 inch (or larger for tiles with more size variation). Additionally, TCNA guidelines for long plank tiles recommend that the offset between planks in a running bond pattern not exceed 33 percent (roughly one-third offset), specifically because plank warpage causes lippage when planks are offset closer to the middle (a 50 percent brick pattern).

In plain terms: many manufacturers and the TCNA lean toward 1/8 inch or wider for plank tile, and going down to 1/16 inch may fall outside recommendations and even void some tile warranties. Always check the specific tile’s printed instructions before committing.

The Warpage and Lippage Problem

Long wood-look planks are not perfectly flat. Manufacturing causes a slight bow along the length, and the longer the plank (some run 48 inches or more), the more pronounced the crown in the middle. When you offset planks in a brick pattern, the high center of one plank meets the low end of the next, creating lippage. Two things fight this:

• A larger grout joint (1/8 inch) gives room to average out the height difference gradually.
• A smaller offset (one-third rather than one-half) keeps the high center away from the neighboring plank’s end.

This is why installers who want tight 1/16 inch joints also need very flat tile, a dead-flat subfloor, and often a leveling clip system to hold adjacent planks even during curing.

Grout Color: The Real Secret to Realism

Joint width matters, but grout color matters just as much for the wood illusion. Choosing a grout that closely matches the tile’s base tone makes even a 1/8 inch line nearly disappear. A contrasting grout, on the other hand, highlights every joint and turns the floor into an obvious grid regardless of width. For the most seamless wood look:

• Match grout to the mid-tone of the plank rather than the lightest or darkest streak.
• Consider a slightly darker grout, since it hides dirt and reads as the natural shadow between boards.
• Use an unsanded or fine-sanded grout appropriate for the joint width (sanded is typically required at 1/8 inch and wider).

Which Should You Choose?

For most homeowners, 1/8 inch is the smart, safe choice: it looks great, follows manufacturer and TCNA guidance, controls lippage, and keeps warranties intact. Reserve 1/16 inch for situations where you have:

• Rectified, very flat, high-quality plank tile.
• A perfectly flat subfloor prepared to strict flatness tolerances.
• An experienced installer using leveling clips.
• Confirmation that the tile manufacturer permits a 1/16 inch joint.

If any of those are missing, the tighter joint invites lippage that is both unsightly and a trip hazard. When in doubt, 1/8 inch delivers nearly all the beauty with far less risk.

Subfloor Flatness Requirements

No grout width can fix a bad subfloor. For long-format plank tile, the substrate must be extremely flat, generally no more than 1/8 inch variation over 10 feet, and tighter for larger tiles. Use a self-leveling underlayment or patching compound to correct dips and humps before laying tile. A flat substrate is the single biggest factor in avoiding lippage, more important than the grout line width itself.

Common Mistakes to Avoid

• Going too tight without flat tile: 1/16 inch joints magnify warpage into lippage.
• Using a 50 percent brick offset: Drop to a one-third offset to reduce lippage on planks.
• Contrasting grout color: Turns realistic planks into an obvious tile grid.
• Ignoring manufacturer specs: Too-small joints can void the tile warranty.
• Skipping the flatness prep: A wavy subfloor guarantees uneven joints.
• Wrong grout type for the joint: Match sanded vs. unsanded to the joint width.

Installation Tips for Tight Joints

If you do go narrow, tile leveling clip systems (like those from Raimondi, MLT, or Tuscan) hold adjacent planks flush while the mortar cures, dramatically reducing lippage. Back-butter planks for full coverage, use a large-notch trowel, and dry-lay a few rows first to check the offset and joint appearance before setting anything permanently. Take your time keeping joints consistent, since the eye catches variation more than absolute width.

Layout Patterns and Their Effect on Joints

The pattern you choose interacts directly with grout line width and lippage. For wood-look plank tile, the safest and most realistic layouts include:

• One-third offset (staggered): Each plank starts one-third along the previous one. This is the TCNA-recommended maximum offset for planks and keeps the high crown of one plank away from the end of its neighbor, minimizing lippage.
• Random or multi-offset: Varying the start point plank to plank mimics real hardwood and avoids the stair-step look while controlling lippage.
• Herringbone and chevron: Beautiful but demanding, since the many joints amplify any lippage and require very flat tile and precise setting.

Avoid the 50 percent brick pattern with long planks, because it places each plank’s high center against the neighbor’s low end, which is the classic recipe for lippage no matter how tight your grout joint.

Grout Type and Maintenance

Once you settle on joint width, choose the right grout. For 1/8 inch joints, a sanded cement grout or a modern high-performance grout works well and resists cracking. Many homeowners now choose stain-resistant grouts or urethane and epoxy-based products because wood-look tile often goes in kitchens, entryways, and other high-traffic areas where grout stains easily. Whatever you choose, seal cement grout after it cures to protect against stains, and keep the joints clean so they continue to blend with the plank color. A well-matched, well-sealed grout line is what lets the floor keep passing for wood for years, rather than yellowing or darkening into an obvious grid.

In the 1/8 vs 1/16 grout line wood look tile debate, 1/8 inch wins for most homeowners because it follows TCNA and manufacturer guidance, controls plank lippage, and still looks like wood when paired with a matching grout color. Save the tighter 1/16 inch joint for flat, rectified tile installed by a pro over a dead-level subfloor, and you will get a stunning, durable wood-look floor either way.