Tile: 3x6 French Linen | Design: Karen Tsay | Image: David Tsay
The size of grout lines for tile is something that comes up with just about every tile installation and is a question we are asked almost every day. While we definitely have recommendations for grout size for each Fireclay product line, there really is no set width requirement.
Instead, the thickness of your grout joint should be based on a number of factors including tile size, the amount of variation in the tile, and your desired style or aesthetic.
To help you out, we've put together a list of considerations and an overview of options to help you choose the right grout size for your project.
Things to Consider When Choosing a Grout Size
The Amount of Variation in Size From Tile to Tile
Everything Fireclay makes is made by hand and there can be a considerable amount of variation in size and thickness from tile to tile. For any handmade tile, we always recommend larger grout joints to account for these irregularities (the tile can fluctuate by ~1/8" in size and thickness, in any direction).
When it comes to thickness, our ceramic tiles are ~5/16" thick; our brick is ~1/2" thick, and our glass tile is ~1/4" thick.
The closer you install handmade tile together, the more apparent the size variation will become as shown below. Here you'll see a wider grout joint giving the brick a uniform appearance.
Brick: White Mountains | Design + Photo: K Interiors
Versus a tighter brick install that highlights the inherent character and variation found in handmade tile.
Brick: Lewis Range | Design: Amanda Jane Jones | Photos: Stoffer Photography
Tile Size
The size of your tile should be considered when choosing a grout size. In general, there is more size variation in larger-sized handmade tiles so they need a bigger grout joint for that to be less noticeable and to achieve a more even installation.
Where the Tile is Being Installed
Where you are installing your tile should also be considered when choosing your grout size. For example, floor installations should consider using larger grout lines for more traction. Also, grout size should be considered when there is a difference in the angle of a surface.
If your surface is not level, the grout will slope from one tile to another. You should also keep in mind that when tiling over a corner, your grout joint will open up, and when tiling into a recess, the top of the grout joint will narrow.
Tile: 6x6 Dot Dash 7 Plein Aire Motif, 1x6 Ivory | Design: Amber Lestrange | Image: Cary Mosier
Let's Talk About Grout Size Options
Finished grout lines will vary from 1/16" to 3/16". However, the actual finished grout spacing will vary from 1/8" to 1/4" if 3/16" spacers are used. If smaller spacers, like 1/8", are used it will accentuate the size difference of handmade tile. Note that using the smallest grout joint possible will increase installation time.
3/16"
We recommend a 3/16" grout size for our Ceramic Tile. This thickness leaves room for the natural variation in size, and the perfectly imperfect edges of handmade tile.
Tile: 2x6 Sand Dune | Image: Margaret Austin | Installer: CL Studio
3/8"
3/8" grout space is the industry standard for Glazed Thin Brick. With brick, you will need to know ahead of time what grout space you intend on installing as that will affect how much overage you should order to complete your project.
Brick: Front Range (discontinued; for a similar look, try Absaroka) | Design: Jon De La Cruz | Photo: House Beautiful
Brick: Norman Big Horn | Design + Image: Kelly Brown
1/8"
A 1/8" size is used for our product lines that feature a rectified, clean-cut edge. All of our Handpainted collections feature this type of edge.
A rectified edge allows for smaller grout lines because the tile has been more precisely cut (unlike our other handmade tiles). There is less irregularity with rectified tiles, so less spacing is needed between each piece. A tight, 1/8" grout space will allow the pattern to flow nicely from one tile to the next.
Tile: Kasbah Trellis in Neutral Motif | Design: Patti Wagner | Photo: Meg Cooper Photography
Tile: 6x6 Santiago Warm Motif | Design + Image: Jennifer Carlos, Carlos Architects Inc.
1/16"
We recommend a 1/16" grout size for our Glass Tile. Glass has clean edges allowing for a tight install. We do not recommend installing any of our products tighter than 1/16," but you can always go larger.
Tile: 2x12 Flycatcher Matte | Design + Image: SIN

Tile: 2x6 Sparrow, Falcon, Oriole, + Chickadee Gloss | Design: Benita Cooper Design | Installer: Sunflour Bakeshop
Tips From Our Director of Installation
We tapped Martin Brookes, our Director of Installation, to share his best tips for grout spacing. With decades of experience and national accreditation in tile installation, he understands intimately how grouting handmade tile can pose unique challenges.
“You want to avoid stair-stepping effects, which is a condition where the edges of the tiles become uneven,” Martin advises. “If stair-stepping occurs, it can be difficult to correct and may require reinstallation.”
Here’s how he ensures optimal spacing:
Create a mock-up. “Before beginning installation, I create a small mock-up to visualize how the tiles will fit together and determine the appropriate grout joint width.”
Use horseshoe shims or wedges. “Instead of fixed spacers, use horseshoe shims or wedges to fine-tune the spacing between tiles and achieve a more precise alignment.”
Step back frequently! “During installation, take regular breaks to assess the overall appearance of the tile layout from a distance. This helps you identify any potential issues or inconsistencies.”
Want our award-winning team to take care of your installation? We offer services in select California areas, with plans to expand soon. Book a free consultation with our team here.
Final Thoughts
Again, when it comes to size you should keep in mind that the tighter the grout joint, the more variation from tile to tile will show, which can cause the dreaded stair-stepping effect or, at the very least, the installation to look sloppy.
This is why your tile installer may suggest a larger grout line for a straighter, more professional-looking installation. It is an aesthetic decision whether to go slightly larger or tighter. Today it's very trendy to have minimal grout space-- but that isn't always the best option for handmade tile.
Tile: Padma Black & White Motif | Design: Karen Tsay | Image: David Tsay
Keep in mind that grout serves a purpose-- to fill in voids, make things straight, and also relieve stress. If the grout line is too tight the tile could chip at stress points once the grout dries. Stress from home settling may also be an issue with little grout space.
This is especially important for Glass tile installations as glass is more sensitive to stress cracking than ceramic tile.
Tile: 4x12 Rosy Finch Matte | Design: Project M plus, Oh Joy | Image: Bethany Nauert
Need Professional Advice?
Our friendly tile experts can help answer any additional questions with our signature free design assistance. Fill out the form below and we'll be in touch shortly!