Porcelain vs Ceramic Tiles

Below We Shine the Light on Water Absorption and How Levels Impact Tile Quality...

Porcelain Tile refers to a measured average water absorption across 4 - 6 samples of 0.5% or less (this is a minimum standard, and many porcelains are up to 10 times lower).

Ceramic Tile has a water absorption at higher levels above 0.5%.

The superior lower water absorption of porcelain tile is a result of vitrification that happens when pressed clays, silica and feldspars are fired under intense temperatures of 1200 - 1300 degrees creating an inert, stable and highly durable tile.

Vitrification in tiles refers to a manufacturing process that creates a dense, glass - like surface, resulting in tiles that are durable, low in porosity, and resistant to stains and moisture.

The tile industry moved to porcelain production for floors in the 1990s starting with Italian manufacturers. Chinese and other Asian producers soon followed converting to porcelain

Porcelain floor tiles have significant longevity and performance benefits over ceramic tiles, especially in wet areas like bathrooms and external areas which are subject to moisture and temperature changes. With this industry move porcelain is still recognised internationally as the standard required for all floors internally.

The Firing Process:

In a market where there is often a focus to buy and purchase at cheaper rates, combined with limited understanding of potential issues by some importers, customers are at risk of unknowingly compromising the quality and longevity and performance of tile flooring.

When tiles are not fired at 1200 to 1300 degrees and are not in the Kiln for at least 35 to 45 minutes, an inferior product is produced. Some tiles on the New Zealand market currently have had firing time significantly reduced to only 25 to 30 minutes and possibly at lower temperatures, producing a compromised less dense material that has not been vitrified to an inert state (see above).

Over 20% of floor tiles currently imported from China and marketed as floor tiles are Ceramic not Porcelain!

Water Absorption:

To reach a lower price point some manufacturers are reducing the time in the Kiln thereby saving costs but importantly also reducing the technical performance and producing not porcelain floor tiles, but higher water absorption material graded as 1% to 3% or higher = officially known as ‘ceramic’.  Often these materials are called semi vitreous or similar, but the Official name is ceramic

With the quest for a cheaper price there is also a possibility of a reduction in quality control standards meaning more imperfections in a box or all of one production is placed into a box, without removing reject material. This means customers can unwittingly receive a mix of firsts and second grade products in each box, which is not something we at Tile Warehouse advocate.

Most customers, if made aware of the difference between ceramics and porcelain and what the implications can be, will most likely steer away from the underfired 1 to 3% material as it will affect some or all of the below.

It may be cheaper at the outset but could be costly to fix in the long run!

Possible Effects of Higher Water Absorption Tiles:

• Higher water retention and spore and microbial/mould growth in wet area floors and shower enclosure
• Increased absorption will reduce grout life due to the increased retention of water
• Higher incidence of defective pieces in boxes
• Postproduction warping
• Lower glaze hardness (PEI ratings)
• Reduced warranties from manufacturers
• Possible reduction in engobe which, with increased water absorption, can cause water marking and worse, staining
• You cannot use 1 to 3% water absorption products externally in New Zealand
• Longevity of the tile and system will be reduced compared to a porcelain.

Be aware! Any tile with a water absorption rate above 0.5% is classified as ceramic. Some importers may still label these tiles as “ceramic,” but if you see terms such as vitreous, semi-vitrified, or no specification at all, the tile is unlikely to have the same durability or longevity as porcelain and may come with other compromises.

TILE WAREHOUSE & ARCHITECTURAL SURFACES ARE PROUD TO ONLY IMPORT PORCELAIN FLOOR TILES