Rectified – also known as dimensionally stable – tiles have been cut after firing and usually have crisp, rectangular cut edges for accurate tiling so need extra care when tiling compared to standard tiles. Rectified tiles are not an easy installation as all the tiles need to be set at the same height to avoid lippage; this means that the surface to be tiled needs to be flat and you need to be aware of any high and low spots. Most tiles and especially rectified tiles are squares or rectangles with right angled corners, however, the natural tolerances of construction mean that rooms are rarely square so tiles must be laid independent of the room edges. Many people choose rectified tiles to be able to use narrower grout lines; if this is your purpose you’ll need to use a finer grouting compound than standard, probably sand free to be able to uniformly fill the narrower gap.

Rectified products have increased in popularity over recent times. All of the porcelain tiles designed and produced by The Tile Company are rectified and allow for fine grout joints between tiles resulting in a beautiful and contemporary finished look.

Here are some interesting facts about this material:

Porcelain tile is an extremely strong, durable, scratch and frost resistant material which has similar characteristics as those of a natural stone.

Porcelain tiles are completely recyclable into such building materials as cement, brick or artistic tile mosaics.

Dry set tiles can be reused by removing and installing them in a different place.

Porcelain tiles are very resistant to water, stains, smells and bacteria.

Porcelain tiles contain no sealants, waxes or other chemicals that could release Volatile Organic Compounds (VOC) into the environment.

The durability of porcelain tile alleviates the need for polishing or sealing.

Porcelain tile can be used on any surfaces: floors, walls, countertops, ceilings, pools, tubs, showers, outside walls and even on unstable surfaces, such as boats, for example.

Tile is easy to clean by using the mildest cleaning products and the only tools needed for cleaning are brooms and mops, which contribute to better indoor air quality.

Unlike granite and marble, pathways do not occur when using porcelain tile flooring, which reduces the use of chemicals and equipment to buff and polish.

According to the Tile Council of North America (TCNA) “Life Cycle Cost Study”, porcelain tile costs less per year than all other floor finishes over the life of a building.

It is important to mention that TCNA is one of the most influential non-governmental bodies in the field of manufacture and sales of ceramic and porcelain tiles, so we at The Tile Company are proud to have the majority of our tile collections certified by the above institution which has confirmed their compliance with the highest quality standards set for this type of building material.

Full Body or Through-Body Porcelain Tile
Full Body porcelain tile means that the tile’s colour and texture is uniform throughout the tile, not just along the surface. Full Body porcelain tile is extremely strong, durable and able to withstand freezing temperatures. It is the strongest type of tile. Unless they have a polished finish, these tiles are slip resistant, scratch and chip resistant which makes them ideal for commercial locations. The colour won’t fade and if a tile does chip, the colour is the same underneath, making the chip less noticeable. These tiles can also be installed in homes as flooring, on walls and in wet areas such as bathrooms.

Coloured Body Porcelain Tile
Coloured Body porcelain tiles possess same quality characteristics as the rest of porcelain products (such as water absorption of < 0.50%) and are similar to Full Body tiles, but there is a slight difference between them. Full body porcelain tiles are produced using coloured raw materials that pervade the entire tile, incorporating uninterrupted colour and pattern features seen on the surface all the way through the tile body. Coloured Body tiles are created with continuous coloured stains from the glaze surface throughout the body of the tile.  Synchronizing the colour of both the glaze and body lessens the visibility of any impact chips which may occur. The colour remains consistent throughout the tile, but any surface design does not continue through the tile body.

Glazed Porcelain Tile
The glaze is usually tinted and is a liquid glass layer that is baked into the surface and gives the tile its final colour. If glaze is then polished, the tile must be sealed after installation to make it non-porous. The glaze finish makes the tile stain resistant and provides an infinite number of colour and texture options. Glazed porcelain tiles are the most common variety chosen by homeowners because of durability and the large array of designs available. They can imitate the appearance of natural stones like granite, limestone and slate, as well as metals like aluminium and brass. Some varieties even look like hardwood. Glazed porcelain tiles are admired for their glossy beauty and durability and can be used on any surfaces.

Double Loaded Porcelain Tile
This type of tiles has a different face and body. Double loaded porcelain is manufactured with two layers of porcelain pressed together and then fired. The top layer is pressed to the base porcelain layer under high pressure and makes a thick layer of design on top of it. This top layer is comprised of porcelain clays randomly infused with various colour pigments that create an infinite range of colour combinations and patterns emulating that of natural stones. This bonded porcelain is then fired. As a result of pressing together two colors on the tiles bisque such design layer becomes 3 to 4 mm thicker which makes double loaded tiles very hard and durable, ideal for heavy traffic commercial projects.

Soluble Salt
It is an older and cheaper technology and is meant for tiles placed in low traffic areas. In this process, the yet unfired tile body is given a liquid colour screen-printing to create the design on the tile. It is called Soluble Salt Technology because soluble salt is used for giving the tile a particular pattern and colour. With this technology 2 – 2.7 mm print are penetrated into the tile. Once the tiles have been fired and polished in order to create a glossy surface, approximately 0.7 mm of the soluble print is shaved off, leaving a total print penetration of only 1 to 2 mm. This is the reason why the SS tiles do not possess same resistance and durability characteristics as, for example, the Double Loaded porcelain tiles.

One of the main technical characteristics of high-quality ceramic and porcelain tiles is their high degree of abrasion/wear resistance. There is an international test of surface wear resistance developed by the Porcelain Enamel Institute and known as PEI scale. According to this system, tiles are divided into five groups which we are going to discuss in more detail below.

So, the first category is PEI-I. The tiles with coefficient PEI-I have low wear resistance, and therefore they are suitable only for private apartments and houses for spaces which are not constantly used (bathrooms, for example), but it is not recommendable to lay such tiles in corridors or living-rooms. Next in the list are categories PEI-II and PEI-III. Tiles with these coefficients are more wear resistant. Floor tiles with PEI-II can be used in all residential areas, and PEI-III tiles are suitable, for example, for offices with relatively low traffic. Finally, tile categories PEI-IV and PEI-V are the most durable and wear resistant ones. They can be installed in places with high traffic of people, such as shopping malls, hotels, train stations, subway, etc.

Along with the PEI scale, a very important factor is the MOHS coefficient, which determines the degree of hardness of surface, and hence the degree of resistance to scratches and damage. The material is tested by scratching it with natural minerals and, depending on the obtained results a coefficient on a scale from 1 to 10 is assigned to it, with 10 – the hardest material and 1 – the softest. This coefficient is very important to consider when choosing floor tile. It is advisable that a wall tile would have a MOHS of at least 4 and a floor tile should be at least 6 (or 7 for more demanding areas).

Such scales as PEI and MOHS, as well as other international classification systems, which we are going to discuss in our next posts, without any doubt benefit the customers helping them choose the right material depending on the requirements and features of their project.

Most times this effect is invisible under normal lighting and is only noticed in certain types of low angle natural light. In such lighting conditions a variety of inconsistencies have been noticed, including light cloudy spots, dark shadow spots and ribbons, and wavy areas of inconsistent reflectivity.

However, these characteristics are not symptomatic of the poor quality of the tile. The tiles exhibiting this problem have been classified as “first quality” under existing international standards.

Then what are the reasons of such effects? As mentioned above, it is caused by light. If you observe a ray of light reflecting from a mirror, you will see that a single incoming direction (a ray) is reflected into a single outgoing direction. Such reflection is called a specular reflection. Reflection off a rough surface such as porcelain tile is known as diffuse reflection. It is a reflection when a ray of light is reflected at many angles.

Whilst polished porcelain has a glossy surface, it does not possess characteristics of a mirror and, hence, does not perform as a mirror. The fact that there are parts of the surface of the tile that receive more grinding and polishing can be considered a source of micro deviations from a perfectly flat surface. Several investigations found that shadowing was related to approximately 5,5 micron deviation in flatness. Apparently, such minor divergence should not be considered a defect of the tile, but can cause undesirable visual effects.

Unfortunately, at present, no international polishing standards exist, but the efforts for their development are underway. Perhaps, once such standards are adopted, it will be possible to control and minimize the appearance of the “optical haze” effect.

Very recently, a methodology that involves chemical removing of some of the gloss from the tile, then restoring it with synthetic diamond polishing has been shown to noticeably reduce or completely remove the “optical haze” effect. However, this procedure is very costly and time consuming.

Customers must understand that “optical haze” is an inherent feature in polished porcelain tiles, even though the degree of the problem can vary between tile manufacturers and between colours. The effects of optical hazing can be minimized by careful design planning, such as, the use of curtains and blinds, and a careful placement of furniture.

The purpose of the organization is to expand the market of ceramic tile in North America, as well as to contribute to the establishment of a clear system of certification of quality ceramic products. One of such certification programs is a water absorption test specially designed for porcelain tiles.

As you probably know, according to many international quality standards, porcelain tile is a material with water absorption of 0.5% or less. Anything that does not match this standard cannot be sold as porcelain tile. Unfortunately, at present there still exists some confusion in the market as to what constitutes real porcelain. Such certification programs are some sort of a guiding light for architects, designers, end-users, helping them to avoid mistakes when choosing materials for their projects.

It is well known that porcelain tile is a very durable product with high abrasion, bending, frost resistance, etc., which also makes it more expensive than regular ceramic tiles, but it is suitable for virtually unlimited field of applications. Porcelain tiles can be safely laid outside, even in regions with very cold climate. It is indispensable for the high traffic areas, where such characteristics as wear resistance and durability are crucial. Thus, when selecting a material for your project, it is important to take the right decision, and that is where the TCNA certification helps to decide.

We at The Tile Company are proud to be one of the TCNA certified manufacturers. Our porcelain tiles meet the highest quality requirements for this type of material, including the water absorption of 0.5% or less criterion. All of our collections of glazed porcelain tiles are certified by the TCNA and have a Porcelain Certification Mark, which distinguishes them among all others as the material of the highest quality.