Key Takeaways
- The Mohs scale and PEI rating measure two completely different things. Mohs measures how resistant a tile is to scratching. PEI measures how well it holds up to foot traffic over time. Knowing the difference helps you buy the right tile for the right surface.
- Mohs runs from 1 to 10, and porcelain typically sits between 6 and 8. The higher the number, the harder the surface and the more resistant it is to everyday scratches from keys, furniture, and daily use.
- PEI runs from 1 to 5, and the rating tells you where a tile can be installed. PEI 1 is walls only. PEI 3 works for regular residential floors. PEI 4 and 5 are for commercial and high-traffic spaces.
- A high Mohs score does not mean the tile is rated for floor use. This is the most common mistake tile shoppers make. A tile can be very hard and still not be designed to handle foot traffic. Always check both ratings before you buy.
- For most Ontario homes, you want a PEI rating of at least 3 for any floor tile. For kitchens, hallways, and entryways that see regular daily use, PEI 3 is the minimum. Busier areas may warrant PEI 4.
When you shop for tile at a store in Oakville, Burlington, or Mississauga, you will likely see two ratings printed on the box or listed on the product spec sheet. They are the Mohs hardness scale and the PEI rating. Most homeowners glance at them, assume they mean roughly the same thing, and move on. That is a mistake worth understanding before you commit to a tile.
The two ratings measure different properties entirely. One tells you about surface hardness. The other tells you about wear resistance under foot traffic. A tile can score well on one and be completely wrong for your intended use based on the other.
Here is a plain explanation of what each rating means, how to read them, and why the difference matters when you are choosing tile for floors, walls, or countertops in your home.
The Mohs Hardness Scale
What It Measures
The Mohs scale measures how resistant a tile surface is to scratching. It runs from 1 to 10. A rating of 1 means the material scratches very easily. A rating of 10 means almost nothing can scratch it. Diamond sits at 10 on the Mohs scale. Talc sits at 1.
Porcelain tile typically falls between 6 and 8 on the Mohs scale. That puts it in the same range as steel and harder than most everyday objects in your home. Keys, coins, and furniture legs generally sit below 6 on the scale. A porcelain tile rated 6 or above will resist scratching from those objects under normal use.
What a High Mohs Score Means in Practice
A higher Mohs score means the tile surface is harder and less likely to show visible scratches over time. This matters most in areas where objects drag across the tile regularly. Think kitchen floors near the stove, entryways where shoes come on and off, or mudrooms where dirt and grit get tracked in.
Grit is one of the biggest causes of tile surface scratching. Sand and fine debris act like sandpaper underfoot. A tile with a higher Mohs rating handles that kind of abrasion better than a softer tile with the same appearance.
What Mohs Does Not Tell You
The Mohs scale only measures scratch resistance. It does not measure how well a tile holds up to repeated foot traffic over months and years. A tile can have a Mohs rating of 7 and still not be suitable for floor use. The Mohs scale is a surface hardness test, not a wear test. That is where the PEI rating comes in.
The PEI Rating
What It Measures
PEI stands for Porcelain Enamel Institute. The PEI rating measures a tile’s resistance to wear from foot traffic over time. It runs from 1 to 5. The test involves rolling a weighted cylinder with steel balls over the tile surface and measuring how much the glaze wears away after a set number of rotations. The result tells you how well the tile holds up to people walking on it every single day.
This is a practical test. It is designed to simulate real-world use on a floor, not just measure the hardness of the material itself.
How to Read the PEI Scale
PEI 1: Wall use only. Not suitable for any floor application. These tiles are designed for vertical surfaces where foot traffic is not a factor.
PEI 2: Light residential use only, such as bathroom floors with soft footwear and no outside foot traffic. Not recommended for main living areas.
PEI 3: Suitable for regular residential floors. This covers kitchens, living rooms, hallways, and bathrooms in a typical Ontario home. This is the minimum rating for most floor tile applications in a house.
PEI 4: Heavy residential and light commercial use. Good for busy kitchens, entryways, and mudrooms that see more than average foot traffic. Also used in small offices and retail spaces.
PEI 5: Heavy commercial and industrial use. Restaurants, shopping centres, schools, and office lobbies. Most homeowners do not need a PEI 5 tile, but it is available if you want maximum durability.
Why PEI Matters More Than You Might Think
The PEI rating directly affects how your tile looks five years from now. A tile with a low PEI rating installed on a busy floor will start to show wear in the glaze. The surface becomes dull and scratched-looking in high-traffic paths. You can clean it all you want, but the damage is in the glaze itself, not on top of it.
This is one of the most common complaints from homeowners who bought tile based on looks alone without checking the PEI rating. The tile looked great in the store. After a couple of years of regular use, it started to look worn in the paths people walk most.
The Key Difference Between Mohs and PEI
They Test for Different Things
Mohs tells you how hard the tile surface is. PEI tells you how well it holds up to being walked on repeatedly. These are related but not the same thing.
Think of it this way. A tile with a high Mohs rating resists a sharp object dragging across it once. A tile with a high PEI rating resists thousands of footsteps wearing down the glaze over time. Both matter. Neither one replaces the other.
The Mistake Most Shoppers Make
A tile can have a Mohs rating of 7 or 8 and still carry a PEI rating of 1 or 2. That means it is a hard tile, but it is only rated for wall use. Installing it on a floor will result in visible wear well before the tile should need replacing.
This happens more often than you might expect. Decorative wall tiles and some imported tiles look identical to floor tiles on the shelf. The numbers on the box are the only reliable way to know which is which. If a tile is rated PEI 1 or PEI 2, it does not belong on a floor, regardless of how high its Mohs score is.
How to Use Both Ratings Together
Use the Mohs rating to understand how the tile surface will handle everyday contact with objects, furniture, and debris. Use the PEI rating to confirm the tile is actually rated for the surface you are installing it on.
For a kitchen floor in a typical Ontario home, you want a Mohs rating of 6 or higher and a PEI rating of at least 3. For an entryway or mudroom that gets heavy use, aim for PEI 4. For a bathroom wall or kitchen backsplash, the PEI rating does not apply, and the Mohs rating matters less since the surface is vertical and not walked on.
Practical Tips for Tile Shopping in Ontario
Always Check the Spec Sheet
Both the Mohs rating and PEI rating should be listed on the product spec sheet or the tile box. If you are shopping in a showroom in Oakville, Burlington, or Mississauga and the ratings are not visible, ask for them. A reputable tile supplier will have that information available.
Do not rely on a salesperson describing a tile as “suitable for floors” without seeing the PEI rating yourself. Confirm the number.
Match the Rating to the Room
Different rooms have different requirements. A spare bathroom that rarely gets used can work with PEI 2. A main floor kitchen with kids and pets needs PEI 3 at minimum, and PEI 4 is a reasonable choice. An entryway that takes outdoor foot traffic every day benefits from PEI 4 as well.
Buying a higher PEI rating than you need does not hurt. Buying a lower one than the space requires will show up in how the tile looks after a few years of use.
Porcelain vs Ceramic
Porcelain tile is generally denser and harder than ceramic. That means it typically scores higher on both the Mohs scale and PEI rating. For floor applications in high-traffic areas, porcelain is usually the better choice. Ceramic tile works well for walls, backsplashes, and lower-traffic floors where the PEI rating is still appropriate for the use.
Conclusion
The Mohs scale and PEI rating are both worth understanding before you buy tile. Mohs tells you about surface hardness and scratch resistance. PEI tells you whether the tile is designed to handle foot traffic and how much. A high Mohs score does not make a tile suitable for floor use. You need both numbers to make the right call.
For most homes in Ontario, the rule is simple. Check the PEI rating first to confirm the tile is rated for the surface you are installing it on. Then check the Mohs rating to understand how it will hold up to everyday contact. If both numbers line up with the room you are tiling, you are in good shape.
If you are planning a tile installation in Oakville, Burlington, Mississauga, or Hamilton and want help choosing the right tile for your space, contact Canadian Tile Pro for a quote. We will walk you through the options and make sure what goes on your floor is rated for the job.