What are Technical Tiles?

Although Technical or Engineering Ceramics are properly the hi-tech ceramic composite materials used in aerospace, military and medical applications, the term is used more broadly in the tile business to refer to any high-end tile with tested characteristics that can be specified with confidence by an architect or product specifier even where the application is expected to survive extreme wear or climatic conditions. Technical tiles in this context are invariably true porcelain with a water absorption of less than 0,5% whereas Engineering Ceramics may not even contain clay but alumina, silicide or carbide instead.

What we would call Technical tiles include in particular such products as large format thin tiles used for cladding or thick format tiles used for access floors. These products are specified in even greater detail than normal wall or floor tiles owing to the unique mounting mechanisms used to install them.

International ISO and European EN standards are used to define the most important features of Technical tiles. The most common technical characteristics are as follows:

Regularity
Dimensions/thickness/straightness of corners/ right angles/ flatness
Extremely important for cladding and applications where a smooth bump free surface is required.

Structural features
Water absorption
Water absorbency is dependent on the porosity of the material’s surface. The least porous ceramic material is porcelain, at levels of below 0.5%.

Massive mechanical properties
Resistance to bending
An important distinguishing element of floors is a material’s ability to resist given breakage loads.

Surface mechanical properties
Resistance to scratching
Ceramic materials must be resistant to scratching and wear from foot traffic and the movement of furniture, chairs, wheeled trolleys, etc.

Thermal and hygrometric properties
Resistance to temperature variations; resistance to frost; coefficient of linear thermal dilation
The thermo-hygrometric properties of porcelain stoneware are dependent on its extraordinary density. As porcelain has the lowest porosity among ceramic materials, it absorbs less water and therefore is at less risk of cracking or crackling under pressure caused by the increase in volume of water as it freezes.

Chemical properties
Resistance to chemical products
In order to resist the attack of chemical substances such as those contained in cleaning products or resulting from use of acids in particular working environments, the compactness of the surface of the material (which, in the case of porcelain extends throughout its entire thickness) constitutes a very important quality once again linked with the material’s low porosity. Good porcelain does not contain microscopic cracks that can permit penetration and stagnation of aggressive substances. This is aided by the high firing temperatures reached in ceramic kilns (1200°C), permitting achievement of greater chemical inertia.

Lightfastness
The chemical and physical properties of Technical tiles require lightfastness of colour. The need to test this property is demonstrated by the fact that Technical tiles are used in outdoor flooring or on the façades of buildings, where the material is exposed to sunlight for prolonged periods. 

Safety features
Coefficient of friction 
A floor’s slipperiness determines the safety of people walking over it and is therefore an essential requirement in commercial and industrial floors.
The slipperiness coefficient, represented by the value “R”, refers to a method which classifies products on the basis of their friction coefficient in response to the specific requirements of a given environment. The higher the friction coefficient, the less slippery the floor.
The standards distinguish between the slipperiness of floor surfaces in areas where people walk with their shoes on (R9-R13) and with bare feet (A,B,C).

R9 - entrances and stairways accessed from outside; restaurants and canteens; shops; clinics; hospitals; schools.
R10 - shared toilets and showers; small kitchens in restaurants and cafés; garages and basements.
R11 - food production facilities; mid-sized kitchens in restaurants and cafés; working environments where there is a lot of water and sludge; laboratories; laundries; hangars.
R12 - production facilities for foods rich in fats such as dairy products, food oils, cured meats; large kitchens in restaurants and cafés; industrial areas where slippery substances are used; carparks.
R13 - places where large quantities of fats and oils are used; food processing areas.

In the presence of water, where people walk barefoot, the flooring is subject to even more restrictive requirements.

A - dressing rooms; areas accessed barefoot.
B - showers; swimming pool sides.
C - sloped swimming pool sides; steps for climbing into pools.

Beyond Technical
There are of course many further technical features that may be specified and required by an architect or specifier developing a project. These could include such diverse features as the material's ability to absorb pollutants, photovoltaic efficiency, thermal or sound insulation effectiveness, light emitting characteristics. We'll discuss some of the more esoteric qualities of ceramic tile in future posts.


We are currently planning a KREM Technical catalogue specifically aimed at architects. Any suggestions for product or technical content to be included are welcome. Contact us here.