Porcelain stoneware is the name given to single-fired, dry-pressed, generally unglazed ceramic tiles with a very low water absorption rate.
Porcelain Stoneware Flooring
A name widely used for unglazed ceramic tiles with a very low water absorption rate. Body stains are added to the tile body to colour them. These tiles can be used just as they are after firing or else the top surface can be polished to give it a smooth, shiny finish. The top surface can also feature embossed patterns for decorative purposes or non-slip protection.
Porcelain stoneware is the most recent type of ceramic tile to become available on the market available on the market. Spain manufactures a wide variety of such tiles and the demand for them is growing. There are two basic types:
- Unglazed porcelain stoneware, for which the name through-body porcelain tiles has become widely used, with an extremely low water absorption rate (less than 0.1%). The top surface is the upper part of the actual tile body and it can be plain coloured or decorated. The tile body can be fired only, (natural porcelain stoneware) or polished to a greater or lesser degree to make it smooth and shiny (polished and satin porcelain stoneware). The top surface can have an embossed pattern for decorative purposes or embossed diamond-shaped dots, grooves or angles to provide non-slip protection when used on outdoor floors or in industrial premises.
- Glazed porcelain stoneware, with a very low water absorption rate (threshold 0.5%). The top surface is covered in a vitreous coat that can be single coloured or decorated. The colour of the tile body varies, depending on the type of product, and it has a very fine, uniform texture, with no heterogeneous elements visible to the naked eye (unless added intentionally).
The surfaces and edges are even and well finished, except in the case of dry-pressed tiles with an intentional rustic look or extruded tiles.
Most tiles are square or rectangular in shape. The usual formats tend to vary from 15x15cm to 60x120cm. Complementary tiles used with them comprise lintels, insets, step tiles and skirting tiles.
Dry-pressed porcelain stoneware tiles fall into group BIa (dry-pressed ceramic tiles with a water absorption rate of E<0.5%) in accordance with standards ISO 13006 and EN-UNE 14411, Appendixes G and A. Spain has proposed the creation and inclusion in the standard of a group called group AIa (extruded ceramic tiles with a water absorption rate of E<0.5%).