Porcelain means 0.5 percent water absorption or less
Porcelain tile is made from clays that fire dense. By the Tile Council's definition it absorbs 0.5 percent water or less. Non-porcelain tile absorbs more than 0.5 percent. Low absorption usually goes with frost resistance, and the FAQ says that is not always true. The manufacturer's own literature is the place to check frost resistance.
Glaze, slip, and cutting
Both glazed and unglazed porcelain exist. Glazed surfaces are usually a little easier to keep clean because microscopic holes are filled. Unglazed porcelain may offer better slip resistance. Non-porcelain tile is often glazed, with unglazed quarry tile as the exception, and it is usually easier to bond and to cut. Porcelain is harder to bond and harder to cut. That difference matters to the installer more than to the person walking on a finished floor, provided the setting materials match the tile.
Through-body color
Some people call unglazed porcelain through-body because the color continues through the thickness. The FAQ says that body is durable and the color does not sit only in a surface layer. Many glazed porcelains are also very resistant to abrasion even when the glaze color differs from the body.
Source
Fetched 2026-10-11 from Tile Council porcelain versus non-porcelain FAQ. The sentences above follow that page. They are not a contractor promise.
Related notes
- Tile notes index
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- A porcelain mark is a tested absorption claim
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