Tile | How It's Made

Being familiar with ceramic tile construction helps you understand and evaluate its performance aspects: why certain ceramic tile floors wear better and longer. The main ingredients of ceramic tile and its general manufacturing process have not changed that much throughout the centuries.  All ceramic tiles are created from natural products extracted from the earth that are shaped into tiles and then fired in kilns at extremely high temperatures.

2 main types of tile construction:

Glazed

• from the side, see 2 layers
• body – called the bisque
• top layer – called the glaze
• hard non-porous, impermeable surface after firing
• more stain resistant than unglazed
• easy to clean
• consider for areas like the kitchen and baths

Unglazed

• solid colored all the way through
• do not have a top layer of glaze
• referred to as through-body construction
• no additional surface applications
• more dense and durable than glazed
• suitable for interior and exterior applications
• good for areas with kids

There are 5 steps in the ceramic tile manufacturing process:

Mining

• process begins with the mining of the raw materials
• mixture composed of clay and minerals

Blending and Mixing

• introduces mud into the mix
• clay and mineral mixture blended and mixed into a semi-fine powder
• water is added to form a wet slurry or mud-like consistency
• the slurry is pumped into a large dryer
• result- fine clay powder that feels like warm, fine sand

Pressing

• applies pressure to the process
• clay is pressed or formed into a tile shape
• pressed tiles are called green tiles
• another method called extrusion replaces the pressing step
• extruded tiles are formed by forcing the clay through a mold versus pressing the tile
• pressing is the more common method used today
• after the green tiles are formed they are dried

Glazing

If the tile is to remain unglazed it skips this step and goes directly to the firing kiln. 

• liquid is prepared from a glass derivative called frit and colored dyes
• applied by a high-pressure spray or poured onto the tile

Firing

• fired in the kiln at temperatures around 2,000 degrees Fahrenheit
• monocoturra tile or single fired -tiles that are fired once after the glaze is applied
• biocuttura or double fired- first fired after the green tile is dried and fired again after the glaze is applied

Alternative- porcelain

• made up of 50% feldspar
• fired at a much higher temperature
• harder and denser
• high performance
• low water absorption ratings of less than 0.5 percent
• can be used for interior and exterior applications or commercial areas

After the finished tiles have been inspected for quality assurances, they are packaged, crated and ready to be shipped.

Uses

• not all ceramic tile is suitable for each area of your home
• tile on your kitchen backsplash may not be recommended for installation on the floor

Rating System

• rating system provided
• rating system found on samples or boxes
• most common system rates ceramic tile abrasion resistance or the overall durability of the tile

5 Classes

Class 1
No Foot Traffic

Class 2
Light Traffic

Class 3
Light to moderate traffic

Class 4
Moderate to heavy traffic

Class 5
heavy/extra heavy traffic

Class 1: no foot traffic

• interior wall applications only and not for the floor

Class 2: light traffic

• interior wall applications and for residential bathroom flooring only

Class 3: light to moderate traffic

• for residential floor and wall applications including bathrooms, kitchens, foyers, dining rooms and family rooms

Class 4: moderate to heavy traffic

• residential, medium commercial and light industrial floor and wall applications including shopping malls, offices, restaurant dining rooms, showrooms and hallways

Class 5: heavy/extra heavy traffic

• can be installed anywhere

Slip Resistance Rating

• measured by its Coefficient of Friction (COF)
• higher the COF the more slip resistant the tile
•  important  for areas that get wet

Other ratings

• scratch resistance
• moisture absorption
• chemical resistance
• breaking strength