Neither label makes a tile better on its own. Porcelain is ceramic tile. What separates the two in the porcelain vs ceramic tile comparison is a measured number: a tile that tests at 0.5% water absorption or less can be deemed porcelain. That is the line the Porcelain Tile Certification Agency uses, as described by ASTM International.
Order by the word on the sample card and you can end up with tile that isn’t suited to its spot. Changing it after it’s set can mean tearing it out. And a shower adds a second question the tile can’t answer at all.
So your job at the sample wall is narrower than picking a side. Find out what the label measures, ask what each tile was made for, and keep the shower’s waterproofing as its own decision. Settle all three with your design team in front of samples, before the tile is ordered.
Is porcelain a different material from ceramic?
No. Porcelain is a ceramic tile, not a separate material. The thing that sets it apart is a water absorption test. That result is the determining factor for whether a ceramic tile counts as porcelain, so the difference lives in a lab report, not in the name on the sample card.
The dividing line is 0.5%. A tile tested for water absorption at 0.5% or less can be deemed porcelain by the Porcelain Tile Certification Agency. Test above that line and the tile isn’t porcelain. It’s still ceramic tile, and it may be made for exactly the spot you have in mind.
That water absorption test is also the basis for how tile products are classified in the industry standard, ANSI A137.1. So the word porcelain points to a measurement taken in a lab, which is why it’s fair to ask to see the number. It tells you a tile cleared one bar. It doesn’t tell you which bar matters in your bathroom.
The label isn’t a style tier. Color and finish come from how a tile looks. The porcelain label comes from a lab result. Two samples can look alike and still land on opposite sides of the line.
What the number tells you, and what it doesn’t
Water absorption is one of the things that standard measures. It also covers breaking strength, coefficient of friction, surface flatness and dimensional tolerances. Those are measured separately, so one number answers one question.
The number describes the tile itself. It says nothing about the grout joints, and nothing about what sits behind the tile in a shower wall. It also doesn’t tell you whether that product was made for a floor, a wall or a shower. That’s a separate question, and the maker’s product data is where to look.
Does every bathroom floor need porcelain?
No, not as a blanket rule. The Tile Council of North America, which wrote that ASTM article, gives simpler advice: select the correct tile for the use and, of course, one you like. Correct for the use is the test. Porcelain is one way to get there, not the requirement.
As a general rule, a lower absorption number can matter more where a surface stays wet, such as a shower floor or the floor beside the tub, and less where water doesn’t reach. It’s a judgment about the location, not about the word on the card.
So one question doesn’t cover it. Ask what the tile tested at, and ask what the maker made it for. Both answers should be in the maker’s product data, so ask for that in writing while you’re still choosing.
The floor and the walls are two different questions too. Tile in a bathroom can land on the walls, the shower floor, a tub surround, a shower enclosure or a backsplash, all places Guthrie’s flooring and tile services page lists for tile. Put the question to each surface on your plan, one at a time, and ask whether the tile you like is made for the floor, the walls or both.
Does porcelain keep a shower dry?
Not by itself. The Tile Council of North America puts it bluntly: grout joints are not waterproof. In a wet area such as a shower, you rely on the method and the substrate, the surface the tile is set on, to protect adjoining areas from water. The tile sits on top of that work.
The Council also lists showers among the areas that require proper installation or a failure can occur. That’s a statement about how the work gets built, not about which tile goes on it.
Tile size shifts the amount of grout. Smaller tiles mean more grout joints per square foot, and larger tiles mean fewer. Because grout joints aren’t waterproof either way, the method and the substrate matter at any size.
So ask the person building the shower how it will be waterproofed. The tile type doesn’t answer that. You’re asking about the build, and the build is what protects a wet area from water. The sequence of work that happens out of sight is covered in how a tub-to-shower conversion is built behind the tile.
Porcelain vs Ceramic Tile: Questions to Ask at the Sample Wall
Four questions cover the ground, whatever the sample card says.
- Ask whether this tile can be deemed porcelain, and what its tested water absorption is.
- Ask what use the maker made it for, whether that’s a floor, a wall or a shower, and whether the same tile suits both the floor and the walls.
- Ask for the maker’s product data in writing instead of relying on the label or the look of the sample.
- Ask how the tile’s size changes the number of grout joints you end up with.
Ask them with the samples in front of you. Seeing tile in person is the point, because a finish can read differently in your hand than on a screen.
Choose the Tile With the Rest of the Bathroom Plan
Tile questions belong before the order, and before the shower gets built. Tile that’s already set can’t be swapped without tearing it out, so the moment to change your mind is while it’s still a sample on the table.
Picking tile early is part of why the order a bathroom remodel should follow puts selections near the front. Once the tile is chosen, the schedule can form around real lead times.
One more decision rides along with it. A floor heater sits under the tile, so whether a heated floor belongs under the tile is a question to settle with the tile choice rather than after it. And if the shower is the part you’re still picturing, Guthrie’s custom tile showers page is the place to see shower tile options.
Frequently Asked Questions About Bathroom Tile
Is ceramic tile a lower grade than porcelain?
No. The porcelain label describes one measurement: water absorption. The same standard measures breaking strength, surface flatness and other properties separately, each on its own. A ceramic tile that tests above the 0.5% line simply isn’t porcelain. That’s a classification, not a ranking, and it says nothing on its own about whether the tile suits your bathroom.
Can one tile go on the shower floor and the bathroom floor?
It can, when the product is made for both jobs. That’s the part to confirm rather than assume. Ask the maker’s intended use for each surface, and look for it in the product data instead of on the sample card. Intended use can differ between the two spots, so check both before you order.
Do color and finish show which kind of tile I’m holding?
No. The porcelain label comes from a lab test of water absorption, so the look of a tile can’t settle it. Two samples can share a color, a finish and a pattern and still fall on opposite sides of the 0.5% line. Ask for the tested number, and ask what the maker made the tile for.
Does smaller tile change what the shower needs behind it?
Smaller tile means more grout joints per square foot. But the Tile Council of North America is clear that grout joints are not waterproof, so the method and the substrate still carry that job at any tile size. Fewer joints don’t remove the question. Ask how yours will be built.
Who should I ask about a tile’s absorption number?
Start with the showroom or design team helping you choose, and ask them to point you to the maker’s product data. The tested number and the intended use should be there. It’s a request worth making before you order, because the label alone doesn’t carry it.
Bring Your Tile Shortlist to the Showroom
The porcelain vs ceramic tile decision gets easier with samples on the table and the product data beside them. At Guthrie’s Pleasant View showroom, you can browse tile samples in person and talk through your project with a member of the design team. Bring the tiles you’re drawn to and the spots you’re trying to fill.
Guthrie’s flooring and tile page says the team can design and install your project, or help with design and product selection if you have your own installer. Either way, these questions are worth settling before the order goes in. When you’re ready, talk with Guthrie’s design team about your bathroom tile.