How to Lay Wall Tiles      DIY Floor Tiling     Technical Guides     Wall Tiles     Floor Tiles     Decorative Border Tiles  

TECHNICAL CHARACTERISTICS

The following summary gives users a knowledge of the typical characteristics and behaviours of ceramic floor and wall tiles. These elements are crucial in selecting your processes and materials. This is a useful informative tool to aid you in choosing your tiles - as there are so many types of tiles on the market.

WATER ABSORPTION

The water absorption is the quantity of water which a ceramic tile can absorb under particular experimental conditions, expressed as a percent in weight of the dry tile. The absorption of water takes place through the pores within the tile - therefore water absorption serves also as a measure of the quantity of these pores. This will provide aspiring tilers with an immediate indication of the structure of the material. High water absorption corresponds to a porous structure, while compact structures have a low water absorption.

DIMENSION AND SURFACE QUALITY

The quality and the value of a tiled surface is directly related to the regularity and uniformity of the individual components. For this reason, all the dimensionsal differences and irregularities in surface quality may alter or disturb the harmony of the tile and its flatness. This can compromise the visual appearance and the reliability of the tiles. It is important to consider the following:

Length Of The Sides And Thickness

The length of the sides and the thickness must be uniform in within one group or lot of tiles, ensuring the regularity of the tiled surface.

Straightness Of Sides

It is important to note whether the sides of your tiles do not curve toards the outside or inside, in the plane of the tile. This will alter the general effect.

Retangularity

The sides must be perpendicular to one another, and shape must similar if not identicle to all of the other included tiles. Straightness of the sides and retangularity are important to assure the regularity of the tiled surface.

Surface Flatness

It is important that tiles you are going to lay have a flat surface, with no waves or distortions. The most effective way to measure and control this characteristic is by looking at the center curvature (from the center to the outer edges), edge curvature (from the center of one edge to the plane in which three of the four corners lie) and warpage (from the fourth corner to any of the other three corners). These dimensional tolerances are generally measured by a percentage, giving the tiler a close idea of the similarity between all tiles regarding the flatness of their surface.

MODULUS OF RUPTURE

The modulus of rupture refers to the measuring of the maximum stress that a tile's surface and material will take without breaking when it is subjected to an increasing load. The modulus of rupture is measured in newtons per square millimeter. It assists a prospective tiler in deciding which tile material to choose, and hence determines whether the tile is capable of withstanding heavy day-to-day loads. It is important to consider two main elements when assessing your tiles:

Characteristic of material, not tile

This measure is provides an estimate of the maximum load for the material of the tile, not the tile itself. For example, if you have two tiles of the same material with different dimensions - say one is twice as thick as the other - the modulus of rupture will be the same however the load necessary to break the thiner tile will be a quarter of that which must be applied to break the thicker tile.

The tested breaking load will always be inferior to the true breaking load

Complex tests are performed to assess an approximate breaking load, they are obtained with results bearing on the conditions and stresses of the load. In a true, daily situation, the breaking load can vary in relation to what will actually cause the load to break - dependent on overlooked factors, and combining elements. The breaking load is a guideline.

SCRATCH HARDNESS

The scratch hardness is a mechanical characteristic of the tile's surface - it assesses the resistance of the surface in regards to daily movement; and how this movement can create scratches and cuts along the surface. These elements can deteriorate the appearance of the tile, particularly in shiny, single coloured tiles. Both glazed and unglazed ceramic tiles are relatively hard and can obtain some scratches, and this obviously only effects the aesthetic quality of the tile surface, not however the funtionality of the tile. Other materials are generally much less resistant, and a large cut to the surface can effect both the appearance and the functionality of the tile itself.

RESISTANCE TO ABRASION

The resistance to abrasion refers to the durability of the tile surface and represents the resistance of the surface itself to wear caused by general movement. Floor tiled surfaces will encompass many different elements crossing over the surface soles of shoes, furniture, trollies or wheels, chairs or other loads that may be moved or dragged across a surface. On a wall tiled surface substances include water, dirt, chemicals, sand or other natural and unnatural sources. Cleaning and maintenance items can also alter the surface such as mops, rags, brooms or detergents. The movement of all of these elements can cause abrasion to the surface of your tiles, and hence decrease the overall appearance of your tiles. Material from the surface of your tiles can be gradually removed via these abrasions, and this can lessen the life of your tiles and make them appear dull. Assessing which tiles are best for you and your environment can be done by categorising which class you fit into:

Class One - Tiled areas that are walked on by soft shoes, socks or bare feet, causing minimal abrasion due to little dirt brought in. For exmaple, bathrooms, where immediate entrance is not from directly outside.

Class Two - Tiled areas in which soft soled shoes or normal footware are worn, with small, occasional amounts of abrasive dirt. For example, living areas.

Class Three - Tiled areas where floors are walked on quite often in normal footware, bringing with them fair amounts of abrasive dirt. For example, kitchens, corrdors and halls.

Class Four - Tiled areas which are submitted to frequent traffic with common amounts of dirt. For exmaple, entrances, work rooms, restaurants or display centres.

LINEAR THERMAL EXPANSION

Linear thermal expansion measures the dimensional changes exhibited by materials as a result of temperature change. Typically, materials tend to expand when the weather warms and contract when the weather cools. Testing for linear thermal expansion is done mathematically, and can be quite a technical process to undergo. It is best to get a professional to assist you when testing for this feature. It is important to note that for each increase in temperature of 1 degrees Celcius, the length of the tile will increase from 4 to 8 thousandths of a millimeter for each meter of initial length.

RESISTANCE TO THERMAL SHOCK

Thermal shock refers to the stress that a tiled area may endure upon coming into immediate and sudden contact with a rapid change in temperature, for example boiling water. The resistance to such an effect indicates whether the tile can withstand such sudden changes in temperature without causing damage to the tiles and their surface and make up. This situation is particuarly signifcant with tiled walls in a shower or bath environment, where the temperature is often making sudden changes.

CHEMICAL RESISTANCE

The chemical resistance assesses the behaviour of a tiled surface upon coming into contact with aggressive or abrasive chemicals, whether accidental or deliberate. Some chemical substances can corrode a ceramic surface and permanently alter a tile's appearance. Chemicals such as acid or strong detergents or bleaches used for extra-ordinary cleaning can often have an impact on the appearance of the tiled surface. Obviously, some chemicals can alter merely the surface of the tile, and can be quickly removed, saving any difficult removal of stubborn substances. However, often very harsh chemicals can seep quickly below the surface of the tile, making it almost impossible to remove the chemical, and hence the chemical continuously can eat away at the material. It is best to assess whether within your home or business you will using aggressive chemicals, and test these chemicals on the material prior to laying the tiles.

CRAZING RESISTANCE

The term 'crazing' refers to the fine hair cracks on the surface of the tile's glaze. Often this fissure can create a circular pattern, and is caused by poor resistance to thermal expansion. Crazing can alter the resistance to your tiled surface quite significantly; meaning that your tiles can be far more prone to other issues. A crazing effect can ultimately change the appearance of your tiles, making them look unusual in relation to the remainder of the tiles.

IMPACT RESISTANCE

The impact resistance of your tiled floor refers to its resilience of heavy blows and sudden impact. It determines whether your tiles will withstand chipping and breaking upon a sudden impact, whether deliberate or not. Typically, ceramic tiles used in the home are not resistant to impact, and will generally crack. It is best in this situation to avoid dropping heavy or sharp objects; those that would not be considered with linoleum or rubber floors. Surface chipping is most dangerous with glazed surfaces, as they are covered with a thin layer of glass. This material is very fragile and prone to cracking and fracturing.