Quality PorcelainWhat Makes a Quality Porcelain Tile? A Specifier's Guide (PEI, Rectified, Full-Body)
A quality porcelain tile has five indicators: water absorption below 0.5% (impervious rating per AS/NZS 13006), a PEI rating of III or higher for floor use, rectified (machine-cut) edges for precise installation, full-body colour for resistance to chipping, and a verified slip resistance rating (P3+ for wet areas under AS 4586:2013).
Not all porcelain tiles are equal. The word 'porcelain' on a box tells you the tile type, it does not tell you whether it is appropriate for your project. Understanding five quality indicators will help you select the right tile the first time.
Water
Absorption
The most important technical specification for porcelain tiles is water absorption, expressed as a percentage of tile weight. Under AS/NZS 13006, tiles are classified as:
| Classification | Absorption Rate | Typical Use |
|---|---|---|
| Impervious (BIa) | < 0.5% | All areas: wet, outdoor, commercial, frost-prone |
| Vitreous (BIb) | 0.5 to 3% | Internal wet areas only (check NCC) |
| Semi-vitreous (BIIa) | 3 to 6% | Internal dry areas, not wet or outdoor |
| Non-vitreous (BIIb+) | > 6% | Wall tiles only, not floors or wet areas |
True porcelain tiles fall in the Impervious (BIa) category. Always confirm the absorption rate from the product data sheet, do not rely on the tile name alone.
PEI Wear
Rating
The Porcelain Enamel Institute (PEI) rating measures surface wear resistance through a standardised abrasion test. The scale runs from I to V:
| PEI Rating | Traffic Level | Recommended Application |
|---|---|---|
| I | Residential wall only | Wall tiles, no foot traffic |
| II | Light residential | Bathroom floors (soft soled shoes, no grit) |
| III | Moderate residential | All residential floors, standard use |
| IV | Heavy residential / light commercial | Kitchens, living areas, retail |
| V | Heavy commercial / industrial | Shopping centres, airports, warehouses |
Select PEI III as the minimum for any residential floor. PEI IV or V for kitchens, high-traffic hallways, and any commercial application.
Rectified
Edges
After firing, tile dimensions can vary slightly (warping, expansion). Manufacturers either:
- ALeave tiles as-fired (non-rectified): variation of plus or minus 1 to 2mm requires wider grout joints (3 to 5mm) to hide size differences
- BMachine-cut the edges after firing (rectified): plus or minus 0.1 to 0.3mm variation allows grout joints as narrow as 1.5 to 2mm
Rectified tiles produce a cleaner, more contemporary look and are required for large-format tiles where dimensional variation is more visible. They are more brittle at the edges, so handle and cut with care.
DW Tiles specifies rectified or non-rectified status on every product listing. For large-format tiles (600×1200 and above), always specify rectified.
Full-Body
Construction
Full-Body Porcelain
The colour and pattern run through the entire tile body from face to back. When the tile chips at a corner or edge, the break shows the same colour as the surface, visually seamless. Preferred for high-traffic areas, outdoor use, and applications where edge chipping is a risk.
Through-Body (Double Loaded)
Two layers of compressed clay with different pigments, pattern extends 4 to 6mm into the tile body. Similar performance to full-body for most applications. Common in rectified porcelain slabs.
Surface-Glazed Porcelain
A glass-based glaze is applied to the tile surface before final firing. The colour and pattern exist only in the glaze layer (1 to 2mm). If the tile chips, the break reveals the lighter body beneath. Suitable for walls and lower-traffic floors, not recommended for heavy-traffic or outdoor use where edge damage is likely.
Slip
Resistance
Under the National Construction Code (NCC), wet areas must meet minimum slip resistance. Australian Standard AS 4586:2013 defines two test methods:
- APendulum Test (P-rating): P1 to P5 for wet conditions, P3 minimum for bathrooms, laundries, and pool areas
- BRamp Test (R-rating): R9 to R13 for oils and heavily contaminated surfaces, used in commercial kitchens and industrial areas
Every DW Tiles product data sheet includes the AS 4586 rating. If you are specifying tiles for a wet area under NCC compliance, request the test certificate.
Quality
Checklist
The following table summarises typical specification values for DW Tiles' porcelain range, based on product data sheets for the 2026 catalogue.
| Quality Factor | Entry-Level | Premium | DW Tiles Range |
|---|---|---|---|
| Water Absorption | 0.3 to 0.5% | < 0.1% | < 0.5% across all lines |
| PEI Rating | II to III | IV to V | III to V (product specific) |
| Edge Type | Non-rectified | Rectified | Both, noted per SKU |
| Body Type | Surface glazed | Full-body / through-body | Full-body and glazed options |
| Slip Rating (Floors) | P1 to P2 | P3 to P4 | P2 to P4 (application specific) |
Source: DW Tiles 2026 product data sheets. Values are indicative ranges, always confirm against individual product specification.
Specification
Advice
DW Tiles' trade team provides specification advice on any project. Open a retail account for access to wholesale pricing and technical data sheets.
- Specification advice
- Technical data sheets
- Slip rating guidance
- Wholesale pricing
- Sydney, Melbourne & Brisbane
- 70+ active collections
- Standards Australia, AS/NZS 13006:2017 Ceramic tiles: Definitions, classification, characteristics and marking
- Standards Australia, AS 4586:2013 Slip resistance classification of new pedestrian surface materials
- National Construction Code (NCC) 2022, Volume One, Section F, Wet Areas
- Tile Council of North America (TCNA), PEI Wear Rating Standard
- DW Tiles 2026 Product Data Sheets, dwtiles.com.au (June 2026)