Frost-resistant
A tile which, due to its manufacturing process, does not retain water within its structure and can therefore be exposed to temperatures at which water freezes without suffering any structural damage.
To determine this characteristic, the ISO 10545-12 frost-resistant standard is followed, which involves subjecting a sample – having first been immersed in water – to 100 cycles of temperature changes between -5°C and +5°C. If no damage is observed, the tile is deemed ‘frost-resistant’.
Non-slip
This is a characteristic specific to floor tiles and refers to the ability of ceramic tiles to resist slipping or skidding.
There are four classes of slip resistance (Rd) specified by the standards, which we set out in detail on this page.
It is important to know the area where the tiles are to be laid in order to ensure they have the appropriate slip resistance.
Varied
This feature is often sought in floor tiles to avoid a repetitive look, by alternating between a variety of designs. Manufacturers pack them randomly, so in most cases, you cannot choose a specific design.
They are designed so that the final appearance of the paving is varied and not repetitive.
Thickness
This icon indicates the thickness of the ceramic tile. Tiles from the same collection usually have the same thickness to make installation easier.
This detail is important if you wish to combine tiles from different ranges or different manufacturers.
Rectified
Rectified ceramic tiles are those with edges cut at a 90-degree angle; in other words, the edges are straight, perfectly cut and of exact dimensions.
This post-production cutting ensures that the dimensions of all the tiles are almost exact, allowing for much neater and tighter installations at the joints.
When laying rectified tiles on floors, it is recommended to use ceramic levelling systems to ensure that all the tiles are properly interlocked with one another.
Irregular edges
Ceramic tiles with irregular edges are those whose edges are not completely straight.
Flooring and wall tiling
Ceramic tiles bearing this icon can be installed as either floor or wall tiles.
By definition, all ceramic tiles manufactured for floor use can be used as wall tiles.
Conversely, ceramic tiles manufactured for wall cladding are not suitable for use as floor tiles.
This is because floor tiles must meet higher standards of resistance to wear, abrasion and all the potential stresses and strains a floor may face. Wall tiles, on the other hand, need only meet minimal technical requirements to maintain their integrity for years.
Flooring
Ceramic tile suitable for installation as flooring only.
Normally, it could be installed as wall tiling, but it may have certain characteristics that mean the manufacturer only recommends it for use as floor tiling.
Wall tile
Ceramic tile suitable only for wall cladding. Its technical characteristics make it perfect for wall cladding, but at the same time rule out its installation as a floor covering in any room.
Cannot be used for flooring.
Matt
A non-glossy ceramic tile. It does not produce reflections from different angles of light.
Gloss
A glossy ceramic tile, which produces reflections as the light hits it at different angles.
Mottled
A ceramic tile where the pattern is characterised by variations in colour tone from one tile to the next.
Some tiles are lighter, others darker, and others of intermediate shades, thus creating an alternating effect in the overall finish.
Manufacturers usually specify the degree of colour variation as low, medium or high.
What properties or characteristics should ceramic tiles have?
Generally speaking, there are four key properties you should be aware of when it comes to ceramic tiles:
WATER ABSORPTION
The first and most important is water absorption. Together with the colour of the raw material, this is the quality that gives ceramic tiles their name. Furthermore, properties such as frost resistance depend directly on it as well. They are known by the following designations:
- PORCELAIN STONEWARE: Ab < 0.5 – Interior and exterior walls and floors
- THICK-BODIED STONEWARE: 0.5 ≥ Ab > 3 – Indoor and outdoor walls and floors
- GLASSED STONEWARE: 3 ≥ Ab > 6 – Interior floors and walls
- TERRACOTTA: 6 ≥ Ab > 15 – Interior and exterior walls and floors (Not frost-resistant)
- TILES: Ab ≥ 10 – Interior walls
FROST RESISTANCE
It is essential to know whether the tile to be laid will be frost-resistant or not. This property is necessary for outdoor installation.
To determine this characteristic, the ISO 10545-12 frost resistance standard is followed, which involves subjecting a sample—after first immersing it in water—to 100 cycles of temperature changes between -5°C and +5°C. If no damage is observed, the tile is deemed ‘frost-resistant’.
SLIP RESISTANCE
This is a characteristic specific to floor tiles and refers to the ability of ceramic tiles to resist slipping or sliding.
There are four classes of slip resistance (Rd) defined by the standards:
- Rd ≤ 15 Class 0
- 15 < Rd ≤ 35 Class 1
- 35 < Rd ≤ 45 Class 2
- Rd > 45 Class 3
See the minimum classes required for floors depending on their location.
Dry inland areas:
- Surfaces with a gradient of less than 6% – Class 1
- Surfaces with a gradient of 6 per cent or more and staircases – Class 2
Damp indoor areas, such as building entrances, covered terraces, changing rooms, showers, kitchens, etc.
- Surfaces with a gradient of less than 6% – Class 2
- Surfaces with a gradient of 6 per cent or more and staircases – Class 3
Indoor areas where, in addition to water, other substances (oils, lubricants) may be present, such as commercial kitchens, abattoirs, industrial premises, etc. – Class 3
Outdoor areas. Swimming pools and showers (areas intended for barefoot users and at the bottom of pools where the depth does not exceed 1.5 m) – Class 3
RESISTANCE TO WEAR, ABRASION AND SURFACE HARDNESS
Resistance to wear and abrasion: This is the method for measuring the ability to conceal wear caused by abrasion, such as that caused by footwear.
There are 5 levels:
- Level 1 – Low
- Level 2 – Medium
- Level 3 – Medium-High
- Level 4 – High
- Level 5 – Very High
Hardness or scratch resistance: To determine hardness or scratch resistance, a test is carried out by scratching the surface with the 10 materials on the Mohs scale in ascending order. The minimum requirement for cladding is Mohs 3 and for flooring is Mohs 5.