Tile Glossary

Abrasion resistance

Is the degree to which a floor tile’s surface will withstand friction (the wear of foot traffic; resistance is determined by abrasion tests. (AS 4459-7) classifies tiles from Group 1 (suitable for light residential traffic) to Group 5 (suitable for commercial traffic).


The quantity of water a tile can absorb expressed as a percent of the dry tile weight. High water absorption corresponds to a porous structure, while compact, vitrified structures feature low water absorption.


Is a substance capable of holding materials together by surface attachment, Note: Adhesive is the general term used and includes cement, glue, thin-set and paste. All of these terms are loosely used interchangeably. Various descriptive adjectives are applied to the term adhesive to indicate certain characteristics as follows: (a) Physical form, that is liquid adhesive, tape adhesive, (b) Chemical type, that is, silicate adhesive, resin adhesive, (c) Materials bonded, that is, paper adhesive, metal-plastic adhesive, can label adhesive, (d) Conditions of use, that is, hot-setting adhesive.

Basalt (Bluestone)

A hard blackish coloured volcanic rock composed of fine-grained plagioclase feldspar and ferromagnesian minerals. The term ‘Bluestone’ is often referred to in Victoria, Australia as ‘Basalt’, but elsewhere it has been used to describe other bluish sedimentary rocks such as dense feldspar sandstones or siltstones.


Layer of mortar that covers the substrate and which is often graduated to floor wastes in wet floor areas, onto which tiles can then be fixed.


Literally ‘Two Firings’ refers to the separate firing of the tiles clay body and the glaze. Bicottura glazes are not as scratch resistant and are now only used on walls.

Body (Of Tile)

Is the structural portion of a ceramic article such as the clay material or mixture, and is distinct from the glazed portion.

Bullnose tiles

Tiles featuring a rounded edge used to finish wall installations, turn outside corners or applied to the leading edge for some steps.

Clinker tiles (Also Known as Klinker)

Is a natural clay tile, generally extruded and unglazed, vitrified or impervious to moisture and therefore suitable for indoor and outdoor use.

Cove tiles

Cove tiles have a radius on their bottom edge and a rounded, finished top edge; they are typically used to provide a practical and easy-to-clean junction between the floor and wall surfaces in commercial applications such as hospital and commercial kitchens etc.


Crazing is a network of fine hair-like cracks that appear in circular patterns across the surface of an individual tile. It is caused by differing rates of expansion between the tile body and its glazed surface. Modern manufacturing techniques have made this a rare occurrence these days, however it may still occur in some low fired, translucent glazed tiles however is not considered a fault but a characteristic limitation of the technology being used.

Decorative tile

Ceramic tiles that have been embellished by means of hand painting, silk screening, decals or other techniques.

Double charged

This is a popular choice because it gives the look of natural stone such as marble and granite, but with the strength of a full porcelain tile. They’re so called because two different layers of porcelain clay are fused together during the manufacturing process.

Dust-pressed tile

Tiles formed by the compaction of finely milled raw materials in moulds before firing. The majority of indoor tiles are produced this way.


Is a crystalline deposit that sometimes appears on the surface of grout joints or unglazed tiles as a whitish powder or crust, caused by moisture reacting with mineral salt impurities in the mortar.


Resin material used in mortars and grouts for thin-set tile installations.

Epoxy Grout

This is a two part grout system consisting of epoxy resin and epoxy hardener. It has impervious qualities that provide stain and chemical resistance. It is used to fill joints between tiles and is especially suited to commercial installation

Expansion Joint

Separation provided between adjoining parts of a structure to allow movement at stress points and to accommodate the expected expansion inherent in ceramic tiles, in order to prevent cracking.

Extruded tiles

Tiles formed by the extrusion process wherein the still malleable or plastic raw clay is forced through a mould and then cut into shape before firing.


This refers to the textural or visual characteristics of a tiles surface. For glazed tiles this may be high gloss, satin or matt. Generally for porcelain tiles, the finish can be natural, polished, semi-polished, honed, lapped. Other finishes mimicking stone such as bush hammered are also available. Other effects include raised, embossed, dimpled, etched, scored, ribbed, etc.


Final step of tile manufacturing process when raw material is ‘baked’ at high temperatures (up to 1250 degrees C for porcelain tiles) to harden the tile body and glaze (if present).


The size of tiles or mosaics may vary from 10mm x 10mm to 3000mm x 1500mm. Format is a modern term that simply refers to size.

Frost resistance

Ability of certain ceramic tiles to withstand freeze/thaw conditions with minimal effect. Frost resistance of ceramic tile is dependent on the tile’s porosity and water absorption levels.


Glassy opaque or transparent coating fired or fused on to the ceramic tile body, creating an impermeable surface.

Glazed porcelain

This tile has a porcelain ‘biscuit’, or foundation, over which a ceramic is applied (Glaze), to give the look of, for example, terracotta, but with more durability. This is now the most popular type of indoor floor tile. They are dense, strong and best cut with a wet saw.

Glazed through-body porcelain

A glazed through-body tile mixes a pigment into the porcelain so the biscuit looks the same as the glaze. This is to counter one the drawbacks of normal glazed porcelain, in that the surface glaze has the same drawback as a normal ceramic tile – if it chips, then you’ll see the differently coloured porcelain biscuit underneath. With the through-body porcelain, this will not be as noticeable.


A visibly granular, igneous rock ranging in colour from pink to light or dark grey and consisting mostly of quartz or feldspars, accompanied by one or more dark ferromagnesian minerals. Granite, which is denser in than marble, is frequently used as a bench top material, and as wall and floor tiles.


A rich or strong cementitious or chemically setting mix used for filling tile joints, which can come is a variety of colours.

Grout joint

Space left between tiles to be filled with grout and intended to accommodate size variations from tile to tile in order to maintain straight lines of installation and allows for some expected movement within the tiling system. This space may be extremely narrow or wider depending on the required installation and/or its aesthetics.

Impact resistance

This is the ability of a ceramic tile to resist breakage – either throughout the body or as surface chipping or as the result of a heavy blow. In general, ceramic tile is not a resilient material, and care should be taken to avoid dropping heavy or sharp objects on its surface. Glazed tiles are more susceptible to surface chipping than unglazed tiles.


Small, sometimes decorative tiles used in combination with larger or plain tiles to create patterns. Small square inserts are also known as a taco or tozzetto.


A rock of sedimentary origin composed principally of calcium carbonate (the mineral calcite), or the double carbonate of calcium and magnesium (the mineral dolomite), or some combination of these two minerals (ASTM CII9). (Recrystallised limestone, compact microcrystalline limestone and travertine that are capable of taking a polish are also included in the category ‘commercial marble’ and may be sold as either limestone or marble).


In finished installations, lippage refers to the condition where one edge of a tile is higher than an adjacent tile. Excessive lippage can cause trips and falls.


This is a narrow decorative border tile, often designed to compliment a range of field tiles.


A true marble is a metamorphosed limestone capable of taking a polish, which exhibits a recrystallised interlocking texture composed principally of the carbonate minerals calcite and/or dolomite. However, some stones in the industry are referred to as green marbles, many of which are composed principally of mineral serpentine and by geological definition, should not be included in the marble definition. (It is important to distinguish between these two types of marbles, since some, but not all, green marbles are dimensionally unstable.) Marble is widely used as a vanity top material and wall and floor tiles.

Modular format

Combining different tile sizes is a popular trend which may be described as ‘modular’. Generally a mixture of sizes from the same tile series are laid together to create a more interesting pattern in the installed tiles. For Example: French Pattern

Mohs’ scale

Scale used to express the measure of a material’s hardness against minerals of known hardness such as Topaz etc; and is expressed in a range from Mohs’ 1 (hardness of talc) to 10 (diamond).


Tiles produced with only one high temperature firing at 1100 Degrees Celsius or above, and which generally exhibit a harder glaze and denser body than twice fired tiles, which are now mostly limited to wall tile production


Monoporosa tiles are single-fired tiles with higher porosity and water absorption levels than ‘monocottura’ tiles. – Water absorption levels typically above 3%.

Mosaic tiles

Mosaic tiles are defined by their size, generally less than 15cm square. Their composition can be Marble, Metal, Glass or Ceramic tiles. They may have a variety of finishes (Tumbled, Polished or Honed for Marble mosaics, – Polished or Brushed for Metal mosaics, – Gloss or Matt for Glass mosaics and Glazed or Unglazed for Ceramic mosaics).


This is a slang term referring to thick-bed mortar consisting of sand and cement.

Pencil tiles

Are narrow tiles (e.g. 20 x 200mm) sometimes with rounded surface, and are used on walls as accent pieces. These are often used in conjunction with capping tiles.

Porcelain stoneware

Are dust-pressed ceramic tiles with water absorption levels of less than 0.5% and offer a high degree of mechanical and chemical resistance. The surface of these tiles may be glazed or unglazed. Often specified for exterior installations, they are also referred to as fully vitrified tiles.


Is the volume of water that a tile can hold relative to its own body weight and is indicative of the tiles internal structure and its likely performance characteristics; for example the lower the porosity the more dense the tile will be and therefore the more mechanically resistant the wear and tear etc.

Quarry tiles

Traditional term for single extruded natural clay tiles with a water absorption level not exceeding 6%. Can be glazed or unglazed.

Rectified Edge/Rectification

This is a manufacturing process whereby the edges of tiles are cut off to improve the dimensional regularity and squareness of the product. These tiles typically exhibit a very square edge, and generally allow installation with smaller grout joints between the tiles.


A sedimentary rock composed mostly of mineral and rock fragments within the sand sized range (from 2 to 0.06 mm) and having a minimum of 60% free silica, cemented or bonded to a greater or lesser degree by various materials including silica, iron oxides, carbonates or clay and which has a compressive strength over 28 MPa (ASTM C119, Quartz-based Dimension Stone Definition II). Australia has vast resources of natural stone; particularly sandstone.


Clear coating applied to protect and prevent the absorption of liquids from spills or staining from other debris. Used with porous materials including: quarry tile, grout, natural stone. Sealers can be topical or penetrative.


A microcrystalline metamorphic rock most commonly derived from shale and composed mostly of micas, chlorite and quartz. Slate is a popular stone that has many applications.

Slip resistant tiles

Tiles designed to help prevent slipping either by adding an abrasive grit to the glaze or a texture to the design of the tile surface structure such as ribs, studs etc.

Note: There is no such thing as a ‘NON- SLIP’ tile!

Slip Resistance Tests

There are 3 main testing methods:

  1. The Wet Pendulum TestThis measures friction between a test surface wet with water and a horizontal moving slider at constant speed.
    Ratings: V (lowest risk) through Z (higher risk) – now replaced by the P rating System P0 –P5 (P5 being the most slip resistant)
  2. Wet Barefoot Ramp TestA test surface is subjected to a continuous water stream and walked on in bare feet, floor is then inclined until the safe limit of walking is reached.
    Ratings: A, B & C
  3. Oil Wet Ramp TestTest floor is coated with engine oil and the test walker wears shoes with soles of a specific rubber composition, hardness & profile. The ramp on which the test surface is affixed is then inclined backwards & forwards until a safe limit of walking is reach.
    Ratings: R9 (higher risk) to R13 (lowest risk)


T-shaped and + shaped spacer, are used to provide consistent sized grout joints during tile installation, and are manufactured in various thicknesses.


Traditional clay used to produce unglazed, cream to red body tiles, generally extruded and 12 mm thick or more. Surface may be rustic, smooth, polished, or waxed.


Has a similar composition to limestone but with holes created by hot springs. Colours include beige, red, yellow and brown, with some variation from piece to piece. The porous holes can be left unfilled and the surface can be simply honed or they can be filled with either a resin or a cement based filler such as grout. The surface of filled travertine can be either Honed or Polished.

Unglazed tiles

Unglazed tiles derive their colour and texture from their raw materials or may be coloured by means of oxides dispersed throughout the body. They are generally fully vitrified.

Vitrified tiles

Vitreous tiles have moisture absorption rates of  less than 3 percent;  whereas Fully Vitrified tiles are made from finer particles and fired to higher temperatures (1250 degrees) which result in a denser tile with extremely low porosity (moisture absorption rates of less than 0.5 percent). Porcelain stoneware tiles are fully vitrified making a layer of glaze unnecessary for the tile to be impervious to water.


An amount of extra tiles added to the exact area requirement and generally in the order of 7 – 10 percent to allow for wastage due to cutting or set out limitations etc. If the installation is complicated or a lot of cutting is involved, the amount for wastage may need to be increased to 15 percent.

Water absorption

The quantity of water a tile can absorb expressed as a percent of the dry tile weight. High water absorption corresponds to a porous structure, while compact, vitrified structures feature low water absorption. (Also relates to Porosity listed above)