Why Bathroom Tile Thickness Matters
Planning a bathroom renovation is not easy! Choosing the thickness of your bathroom tiles is an important aspect of your planning that many people neglect.
Bathroom tiles will usually be ¼ -½ inch (or .64 cm – 1.27 cm). The thickness of bathroom tile determines its strength, so it would make sense to use a thicker, stronger tile on the bathroom floor, with a thinner tile on the walls.
Are there tricks to knowing which tiles are better suited to a particular area, or can any tile be used wherever you feel it fits better? Can a tile be too thick? Read on to find out.
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How Thick Should Your Bathroom Tiles Be?
Knowing the thickness of your new bathroom tiles will certainly come in handy when you are planning how many tiles you need for the space.
Bathroom tile thickness is determined by the choice of material and the tile finish that you choose for the area.
The manufacturer is also a factor as each tile supplier has its own methods to create its signature tile styles.
The thickness of the tile you choose for the space is particularly important. Tile thickness really does matter to ensure the tiles are uniform and even across the surface.
Make sure that you measure the space correctly as the incorrect tiles could lead to unwanted problems:
- Large gaps where the floor tiles and wall tiles meet.
- Uneven flooring if new tiles are not perfectly matched to existing tiles.
- The incorrect tiles for the purpose, e.g., floor tiles that are not thick enough to withstand the amount of foot traffic.
How Many Tiles Do You Need?
When deciding on how many tiles and the thickness of each to buy for your bathroom space, a tile calculator can be very helpful. You can download our free tile calculator. Fill out the form below and I’ll send it straight to your inbox.
Measure Carefully!
When selecting tiles, you’ll need to carefully measure the size of the different surface areas to be tiled, e.g., floors vs. walls. This is particularly important if you already have existing tiles in the bathroom. Matching new tiles with existing tiles is challenging but can be done with careful planning.
Choosing different tile styles and designs for each area could lead to uneven surfaces because of the extra thickness of the tiles. A thicker layer of tile adhesive or grout would need to be used to compensate for the tiles’ different thicknesses and ensure that they will sit flush with each other.
You’ll also want to answer these questions:
- Are there doors, windows, mirrors, or permanent fixtures in the space? Do you want the bathroom tiles to sit flush with the door and/or window frames?
- Are there other tiled areas leading into the bathroom? Should bathroom tiles sit flush along the floor or archways?
Bathroom Tile Slip & Hardness Ratings
Some materials are typically used in the bathroom more often than others simply because of their price, availability, color selection, and durability.
Look for the DCOF (Dynamic Coefficient of Friction) rating to determine whether the surface is safe to walk on when wet. DCOF > 0.42 is considered safe under wet surface conditions.
The PEI (Porcelain Enamel Institute) classifies tiles by the hardness of the glaze and how much weight it can withstand.
- PEI Class 1 (no foot traffic, walls only)
- PEI Class 2 (light traffic, walls, and floors)
- PEI Class 3 (light to moderate traffic, walls, and floors)
- PEI Class 4 (moderate to heavy traffic, residential, medium commercial, light institutional)
- PEI Class 5 (Heavy to extra heavy traffic – residential, heavy commercial, institutional))
The table below is a quick overview of the more popular bathroom tiles, the standard sizes available, and the glaze hardness rating of each tile:
| TILE TYPE | STANDARD SIZE | THICKNESS PER TILE | GLAZE RATING |
|---|---|---|---|
| Ceramic | 16 x 16, 12 x 12, 6 x 6, 4 x 4 | ¼ to ⅜ inches | PEI 2 |
| Porcelain | 16 x 16 | ¼ to ¾ inches | PEI 5 |
| Cement | 8 x 8 | ⅛ to ½ inches | PEI 4 |
| 10 x 10, 12 x 12 | ¾ inches | ||
| Stone | 12 x 12 | ⅜ inches | PEI 4 |
| 16 x 16, 18 x 18 | ½ inches |
Does Grout Affect Tile Thickness?
The amount of tile grout that you use will have an effect on the bathroom tile thickness overall in the available space. Read this article to find out how to calculate the amount of grout you will need for your bathroom.
Generally, a layer of grout or mortar is about 3/16 to 1/8 inches thick, so include this amount in your calculations.
Knowing the difference between the different tile adhesives will help you in deciding how much to use and where to use it:
- Grout. A paste or mortar to fill the gaps and crevices between the wall and floor tiles
- Mortar. A mixture of sand, lime, cement, and water bonds bricks and stones. Generally spread over the wall or floor before laying tile.
- Thinset or mortar. A mixture of cement, fine sand, and water hold the tile to the base. Generally used in wet areas like the shower or for heavier tiles.
- Tile adhesive. A powerful adhesive used to bond tiles to a variety of surfaces.
My post Don’t Forget the Sealer! will answer all your questions on how to seal your grout and tiles.
All tiles should be installed evenly across the space and should all fall in line with each other.
Tiles need to be flush for a reason. If they are not, you could run into the following unwanted problems in your bathroom space:
- Uneven tiles
- Crooked tiles
- Badly fitting tiles
So, the trick to calculating the bathroom tile thickness is knowing what the different sizes of the tiles are, how thick your mortar and grout will be, and the size of the available space.
Does The Substrate Affect Tile Thickness?
The substrate is any surface underneath the tiles. This can be in the form of:
- A subfloor
- Cement board
- Plywood
- Concrete or cement
- Sheet vinyl flooring
The flooring underneath the tiles can certainly increase the height of the tile, especially if a huge amount of grout or adhesive is required to create a flat smooth, even surface for the tile to be fitted to.
The substrate can lift the height of the floor or narrow the size of the space. Be sure to include the additional dimensions of the existing substrate when measuring the floor and wall areas of the room. Include the grout and cement that will be used to secure the tiles to the substrate.
If the floor has already been raised in the past, increasing its height, it might be better to use new thinner tiles rather than thicker tiles in the space.
Match the existing tiles to create even surfaces. Uneven surfaces can cause people to trip and fall in the bathroom, and let’s face it, uneven surfaces are not pretty!
Are Thicker Tiles Better In the Bathroom?
This is a great question and one that deserves a more detailed answer than a simple yes or no. Tiles are used in the bathroom space for many reasons:
- To increase water resistance of the walls and floor. (For more on this, read Are Bathroom Tiles Waterproof? )
- For hygiene purposes to prevent mold and mildew
- To lighten and brighten the space
While thicker tiles might be more useful in the bathroom, there is no reason why you can’t use thinner tiles. Each tile has a purpose for use in the bathroom:
Thicker tiles:
- Thicker tiles are more durable and will last longer than thinner tiles if looked after correctly.
- They are less likely to crack and break than thinner tiles simply because they are thicker and stronger. Regularly treating thicker tiles with sealer will prolong their lifespan and prevent water damage.
- Thicker tiles fit the floor space better and often add to the mood and ambiance of the area by providing the illusion of space, even in a smaller bathroom!
- Thicker tiles can withstand foot traffic on the bathroom floor.
- Thicker floor tiles often have added texture to provide a non-slip surface and to prevent the risk of slipping.
- Thicker tiles are generally cheaper than thinner tiles as they are more cost-effective to make
Thinner tiles:
- Thinner tiles are lighter, smoother, more delicate, and generally more slippery when wet making them the ideal choice for walls, although if the tile has a non-slip surface, it can be used as a floor tile
- Thinner tiles are easier to carry and lift to higher areas when installing
- There is generally a wider range of colors, patterns, and designs in thinner tiles than thicker tiles
Do your research before choosing tiles for your bathroom and make an educated decision before you decide. 17 Beautiful tile materials will give you some great ideas on choosing the perfect tiles for your bathroom!
Top Choices for Thicker Bathroom Tiles
If you want to go with a thicker bathroom tile, consider using glazed ceramic, porcelain, cement, or natural stone:
Glazed Ceramic Bathroom Tiles
Glazed ceramic tiles are water-resistant, ideal for moisture-prone areas like bathrooms. Glazed ceramic tiles are stain and slip-resistant, but they are prone to wear and chipping. They are very easy to clean and maintain, making them durable, long-lasting products!
Porcelain Bathroom Tiles
Porcelain tiles are fired at a higher temperature than ceramic tiles, so they are even harder. They are suitable for high-traffic areas as they are hard-wearing, resistant to stains and scratches, and easy to clean and maintain.
Cement Bathroom Tiles
Generally strong, heavy, and long-lasting, cement tiles are durable, mold-resistant, and can withstand heavy knocks. They are porous and prone to staining, but they are usually slip-resistant, making them the perfect material for a bathroom floor!
Stone Tiles
Natural stone tiles are thick and heavy, ideal for the bathroom floor. They are porous, so they should be treated with a sealant to prevent staining and damage to the surface. Natural stone tiles are beautiful with unique patterns to suit any space!
Read my post about the 7 Best Bathroom Floor Tiles.
Should Bathroom Floor Tiles Be Thicker Than Wall Tiles?
Bathroom floor tiles are designed to carry heavier loads without breaking, so they should be more durable. Bathroom tile thickness is usually directly related to its strength.
If you use thinner tiles on the floor, there is a greater risk of cracking and breaking. Damaged tiles could mean costly and lengthy repairs!
All bathroom tiles should be porous, dense, and water-resistant, but floor tiles should also be slip-resistant to prevent nasty accidents.
As floor tiles are often finished with non-slip textures, they will generally be thicker than a non-treated wall tile.
How To Measure The Required Thickness of Your Bathroom Tiles
It really is important to know the bathroom tile thickness to correctly space the tiles on the floor to the tiles on the wall.
If you don’t get the measurements right, you could end up with large, unwanted gaps and spaces between the tiles or uneven surfaces.
Whether you are using all thick tiles, all thin tiles, or a combination of the two, there is a trick to ensuring that your tiles are laid straight and even along the floors and walls. Measuring the thickness of tiles is easy when you know how:
Tools required:
- A pen and paper to record the measurements
- A measuring tape
- A calculator
Method:
- Measure the thickness of the tiles using the measuring tape
- Add ¼ to ½ inch to the calculation to cater for the backer board and grout
Pro Tip: Measure tile thickness to make sure doors have enough clearance to swing inward or outward.
How to Account for Tile Thickness in the Bathroom
When choosing tiles, always make sure that you select the correct material for the space. Some tile materials are only suitable for walls or floors, while others can be interchangeable and used on both floors and walls.
Before you decide on how many tiles you need and how thick they should be, you need to know the size of the area you will tile.
Follow this quick calculation method to determine the size of the space:
- Multiply the width of the area by the length to get the area in sq feet. Round up to the nearest foot if the area includes a decimal
- If the room is L-shaped, divide the space into two rectangles and measure each individually
- Tiles are sold in boxes per sq foot. Each box will specify the total sq foot that all the tiles in the box will cover. Round up the nearest whole number, for eg
- If the box contains enough tiles to cover 12.5 sq feet and the area for tiling is 100 sq feet, you would need 8 packs of tile to cover the area (100/12.5)
Rule of Thumb for Measuring Tile
A great rule of thumb when choosing tiles is to measure the size of the available floor and wall space and measure how large the open space can be for the tiles.
For instance, if you are installing wall tiles and floor tiles in the same room, make sure that you leave an appropriate gap along the corners big enough to fit either a vertical or a horizontal tile – they will have to meet at the edges somewhere, and if you don’t leave enough space you could well end up unnecessarily trimming down tiles!
Draw a diagram with the floor, walls, and window layout.
A tile calculator can be a huge help. Download my free tile calculator by filling out the form just below. I’ll send it to your inbox.
Bathroom Tile Sizes
Although bathroom tiles are available in many different sizes and shapes, most tiles have standard uniform sizes allowing you to plan which tiles you need to fit your space. Read What size tile is perfect for YOUR bathroom? for more information.
The size of the tile you choose could influence the look and feel of the space – for instance, large floor tiles could emphasize the size of the room, while large tiles used in a small area could give the illusion of more space!
While tiles are available in various shapes, styles, patterns, and colors, the sizes of popular tiles are generally more uniform, following standardized industry sizes.
Does the Thickness of Your Tiles Really Matter in the Bathroom?
Certain areas in the bathroom space should be tiled with thicker tiles, while thinner tiles can be used in others.
When choosing the perfect tile for the bathroom, consider durability, especially for floor tile.
Also, consider the importance of matching new tiles with existing tiles, and how to create an even surface without unsightly gaps between the floor and the walls.
Check out my ultimate guide to bathroom tile, which includes resources about bathroom tile materials, bathroom tile colors, tile finishes, waterproofing bathroom walls and tile, grouts, sealants and more.
Note: If you’re about to embark on a bathroom remodel, get my Save Big $$$ Cheat Sheet. You’ll get a free PDF with designer hacks that can literally save you thousands of dollars. Just fill out the form below and I’ll send it to you.
Tags: bathroom floor tile, bathroom tile, bathroom tile size, bathroom tile slip rating, bathroom tile thickness, how to choose bathroom tile
