A good tile and a cheap tile can look identical in a showroom. The difference shows up two years in, when the cheap one has crazed glaze, lippage at the joints, and a colour drift between boxes that wasn’t there on day one. This guide walks through what to actually check on a tile spec sheet before you buy, so you can tell the difference before it’s grouted into your floor.
Start with the body, not the surface
Tiles fall into a few main categories: ceramic, porcelain, natural stone (marble, travertine, limestone, slate) and glass. The body of the tile — the bit underneath the glaze — is what determines how it wears, how much water it absorbs, and how it handles a dropped pan.
- Porcelain is fired hotter and denser than standard ceramic. It absorbs less water, chips less, and works on floors, walls and outdoor areas. Most floor tiles sold in Australia are porcelain for this reason.
- Ceramic is softer, cheaper, and best kept on walls or low-traffic floors. The glaze is harder than the body, so a chip exposes a paler clay underneath that’s hard to disguise.
- Natural stone is the highest-end look and the highest-maintenance product. Most natural stone needs sealing on install and resealing every 2-3 years.
- Glass is a feature tile — splashbacks, niches, pool waterlines — not a floor tile.
PEI rating: how much foot traffic the tile can take
The PEI (Porcelain Enamel Institute) rating is a 1-to-5 scale that measures how well the surface resists abrasion. The numbers translate roughly like this:
- PEI 1 — walls only.
- PEI 2 — light residential, bathroom floors with bare or socked feet only.
- PEI 3 — most residential floors, including kitchens and entries.
- PEI 4 — heavy residential and light commercial (cafes, retail).
- PEI 5 — full commercial, public spaces.
For a normal Australian home, PEI 3 is the minimum on a kitchen or living-area floor. Anything with a high-gloss finish that’s only PEI 2 will scratch where the dog walks and the chairs scrape.
Water absorption rate
Water absorption is given as a percentage. The lower the number, the denser the tile and the safer it is in wet zones. The standard bands are:
- Under 0.5% — fully vitrified porcelain. Suitable for outdoor use, freeze-thaw exposure, and pool surrounds.
- 0.5-3% — vitrified, fine for any indoor wet area including bathrooms and laundries.
- 3-7% — semi-vitrified, indoor floors and walls only.
- Over 7% — non-vitrified, walls only. Don’t put these on a bathroom floor.
If a supplier can’t tell you the water absorption rate, that’s the answer — assume it’s high. For a deeper view of what actually holds up against water, see our waterproof flooring options guide.
Thickness and format
Standard floor tiles run 8-10 mm thick. Large-format tiles (600 x 1200 mm and bigger) are usually 9-10 mm to keep weight manageable; outdoor pavers run 20 mm. A thicker tile isn’t automatically better — what matters is that the thickness is consistent across the box. Pick a tile up at the showroom and feel the back: a quality porcelain has a flat, evenly ribbed underside. Cheap tiles bow slightly and are noticeably heavier on one corner than the other, which makes them a nightmare to lay flat.
Rectified edges
Rectified tiles are mechanically cut to exact dimensions after firing. Every tile in the box is the same size to within fractions of a millimetre, which lets your tiler run a 2-3 mm grout line and get a near-seamless look. Non-rectified (pressed-edge) tiles vary in size from one to the next and need a wider grout line — usually 4-5 mm — to absorb the variation. For modern interiors with large-format porcelain, rectified is what you want. For a traditional look with a wider grout joint, pressed-edge is fine.
Slip resistance: the R rating
Australian tiles are commonly rated on the R scale (R9 to R13) for slip resistance under wet conditions. Bathrooms, laundries and outdoor areas should be R10 or higher; pool surrounds and external stairs want R11 or R12. A polished porcelain at R9 looks beautiful in the shower and becomes an injury claim the first time someone steps out wet. Match the rating to the room.
Colour and pattern consistency
Tiles are sold in batches (the batch number is on the box). Colour and pattern can drift between batches, sometimes noticeably. Two things to do before install:
- Order all the tiles you need plus 10% wastage from a single batch in one go. Topping up later from a second batch usually means a visible patch.
- Open three or four boxes before the tiler starts and dry-lay a small section to check the variation. Quality tiles are graded V1 (uniform) to V4 (high variation) — V4 isn’t a defect, but it does mean you should mix from multiple boxes during install rather than working straight out of one box.
Pick the manufacturer, then the tile
Italian and Spanish porcelains generally publish full spec sheets — PEI, water absorption, R rating, batch number, thickness tolerance — and stand behind them. A tile sold without a spec sheet is a tile you can’t actually compare to anything else. Established Australian retailers will have those data sheets on hand and will quote in m² with a wastage allowance. If you’re costing a tile job in full, our tiler rates per m² in Australia guide breaks down the labour side.
The short version
For a normal residential floor, you want a porcelain tile, PEI 3 or higher, water absorption under 3%, rectified edges if you’re going modern, and an R rating that matches the room. Get the spec sheet, get the batch number, and order 10% over for cuts and breakages. If you’re picking tiles for a kitchen specifically, our best flooring options for kitchens guide compares tile against the alternatives. We carry a tile range across our Sydney and Brisbane showrooms — bring a swatch of your kitchen joinery and we’ll walk you through what’s worth the money.
Ready to shop? Browse our full tile range online, or drop into our Sydney or Brisbane showroom to see the range in person.