Ceramic and porcelain tiles are firm favourites in South Africa for almost any type of application, and the market is well served by two local manufacturers and a host of importers and distributors bringing the best of European, South American and Chinese products to this country with all the modern trends and technologies that this encompasses.
The reasons for their popularity are not hard to find: they are easy to install; look great in meeting any décor requirement; endure the most exacting work environments and heavy traffic; require minimum maintenance; and last longer than almost any other flooring material.
Qualities and virtues of ceramic tiles
Ceramic tiles are variously sized slabs (with sides from a few centimetres to more than one metre in length, and about 5mm-25mm in thickness), derived from mixes of clay, sand and other natural substances that are fired at very high temperatures. This mixture of raw materials determines the ceramic nature of tiles.
Ceramic materials are very ancient products, but they are still used today in the most advanced and modern applications, with general properties that include exceptional hardness, rigidity, fragility, and inertia.
The hardness, resulting from reactions which occur during the firing phase, is associated with the compact structure and the high level of internal cohesion, while the nature of the chemical bonds gives the ceramic tile very high resistance against breakage. They are able to support high loads without deforming or bending; they are therefore rigid.
Another property connected with the ceramic nature of tiles is their fragility, which defines their behaviour in the event of impacts. Moderately resistant to impact, the ceramic tile does not deform or bend, in contrast to ductile materials.
Also, the high temperature of the ceramic production process creates stable compounds, practically resistant to any kind of reaction with other substances. Ceramic tiles are therefore inert, that is, insoluble and unalterable in contact with water, and with most chemical substances. Even the flames of a fire cannot alter their composition.
However, it is necessary to bear in mind that the undisputed qualities of the ceramic tile, in particular its mechanical and chemical resistance, can only be fully exploited if the tiling has been correctly designed and installed.
Ceramic tiles come in a wide variety of different formats: double-fired; white body single-fired, red body single-fired; clinker; terracotta; porcelain stoneware; red stoneware; and mosaic. Let’s take a look at these options.
Double-fired (also known as ‘Majolica’ and ‘Cottoforte’)
These are glazed tiles, whose production cycle comprises two firings in the kiln – the first for the bisque (the body of the tile), and the second for the glazing. The main applications for this type of tile are in residential projects for interior wall covering (majolica) and interior floors (cottoforte).
These tiles are always glazed with a non-transparent glaze and the cottoforte tiles (which are typically Italian) are double-fired tiles, available in a variety of tile sizes.
This is a product fired at a very high temperature (about 1250ºC), based on the principle of vitrification. It has optimum qualities of resistance to mechanical stress, wear, atmospheric elements and sudden changes in temperature, and is easy to clean and maintain. Clinker may be unglazed or glazed with a single firing.
Clinker has a notable resistance to mechanical, thermo-hygrometric stress and atmospheric agents,and thus can be used for both interior and exterior floor covering, exterior wall covering, sports and swimming facilities, industrial floor and wall coverings, urban furnishing, and raised floors.
Terracotta is a popular ceramic material obtained by extrusion and produced from a mixture of selected clays. After moulding and drying it is fired up to around 1100ºC, and a porous mass product is produced in various shades of reds, pinks, yellows and browns.
It is available in various sizes and shapes, enhanced by a great variety of special pieces. ‘Cotto’ tiles are generally unglazed, but the surface can be pre-treated to facilitate cleaning and maintenance. The product has good resistance to compression, bending, and to chemical and atmospheric agents.
The main applications for Terracotta tiles are interior floor covering, façade covering, particularly suitable for restoration and renovation work on old buildings, outdoor decoration and for improving the aesthetic quality of public areas in city centres.
Porcelain (sometimes known as porcelain stoneware).
Porcelain tile is a product obtained from the dry pressing and firing at very high temperature (up to 1250ºC) of an atomised mixture composed of selected clays, kaolin, quartz and feldspars. The tiles obtained have a high resistance to wear, abrasion, and mechanical stress (intense traffic). They are also frost-proof and resistant to chemical and atmospheric agents, in addition to which water absorption reaches minimum levels.
These tiles can be provided glazed and unglazed; the surface of the unglazed product can have various finishes such as matte, smoothed by mechanical polishing, or textured. Porcelain combines excellent chemical and physical characteristics with particularly interesting colour and decorative effects.
Porcelain tiles are ideal for interior and exterior floor and wall covering, façade covering, curtain walls, and raised floors.
These are unglazed tiles with a compact red bisque, obtained by pressing. They have low porosity and excellent mechanical and chemical resistance, as well as resistance to frost and atmospheric agents. The main application for red stoneware is in interior and exterior floorcovering.
White body single-fired (also known as monoporosa)
These tiles have a white body bisque made from iron-free clays, with the addition of siliceous sands and feldspars. The production cycle requires the simultaneous firing of the bisque and glazing.
These products generally have low porosity and excellent mechanical resistance, as well as resistance to frost and atmospheric agents. Thus they are ideal for interior and exterior floor covering and interior wall covering.
Red body single-fired
Tiles with a red body bisque are made from clays containing iron oxide. The production cycle also requires the simultaneous firing of the bisque and glazing. The porosity of the bisque varies from medium to low, and performance levels, influenced by the properties of the bisque, generally show good physical and chemical properties. Also mostly used for interior and exterior floor covering, interior wall covering.
A material obtained from pressing, available in a wide range of colours and patterns. Each tessera (single element) has a very small surface area, so to facilitate the laying of large surface areas mosaic is sold with the tesserae pre-assembled on a net. The main applications for mosaic include interior and exterior covering, panels and decorative elements.
Acknowledgement and thanks are given to the following for information contained in this feature: www.laceramicaitaliana.it; Ceramic Tiles of Italy; Johnson Tiles.
State of play!
Jeanine Arundale, brand manager of Johnson Tiles (a division of Norcros South Africa), says that while the company has gone through a couple of testing months so far this year, they are still experiencing positive feedback from the market.
“Our brand is strong and with us reinforcing our position, strength and quality we are holding steady,” she says. “New business is on the rise due to the hard work of our sales and marketing teams pushing for new business in certain markets.”
Jeanine says that the locally made porcelain tiles have been very well received, especially in the contracts market due to their inherent benefits and the fact that they are from a trusted local source such as Johnson Tiles.
“The trend we see is towards more natural-looking large-format tiles, particularly glossy porcelain, she says. “The advent of inkjet technology helps to create tiles with any print imaginable – new in South Africa are the wood look-alike tiles – these have the traditional benefits of ceramic tiles but with the warm look of wood – very trendy, though quite costly.”
Jeanine says that the good sellers at the moment are Johnson’s new contractor’s range of tiles – the Sinai range of 500 x 500mm and Karoo range of 400 x 400mm glazed ceramic tiles (these are Builder’s Warehouse exclusives) and also the new 400 x 400mm porcelain tiles, the Module range that has a dry glazed salt and pepper type-finish to make them hardwearing and slip-resistant.
Johnson Tiles will be celebrating 60 years in South Africa in 2012 – a wonderful achievement and milestone for this bourgeoning company, considering its rather humble beginnings.