Ceramic FAQs

Ceramic FAQs

What is the difference between Porcelain and Ceramic Tiles?

The main difference is in the types of clays used. Ceramic tiles are generally made from red or white clay mixtures and then finished with a durable glaze that carries the colour and pattern of the finished tile. They are softer and easier to cut than porcelain. These non-porcelain ceramic tiles are usually suitable for very light to moderate traffic.

Porcelain tiles are generally made by the dust pressed method from porcelain clays which result in a tile that is denser and more durable than ceramic tile. The finish is a finer grained and smoother with sharply formed faces. Glazed porcelain tiles are much harder and are more wear and damage resistant than non-porcelain ceramic tiles. They are excellent for light traffic and heavy traffic.

Where can your tiles be used and what is a PEI rating?

A. PEI classes range from 0 to 5. The Porcelain Enamel Institute rating scale is not a measurement of quality. It is a scale that clearly indicates the areas of use each manufacturer recommends and has designed their tile to fit.

Class 0 – No Foot Traffic:

Wall tile only and should not be used on floors.

Class 1 – Very light traffic:

Very low foot traffic, bare or stocking feet only. (Master bath, spa bathroom).

Class 2 – Light Traffic:

Slipper or soft-soled shoes. Second level main bathroom areas, bedrooms.

Class 3 – Light to Moderate Traffic:

Any residential area with the possible exception of some entries and kitchens if extremely heavy or abrasive traffic is anticipated.

Class 4 – Moderate to Heavy Traffic:

High foot traffic areas where abrasive or outside dirt could be tracked, such as residential entry, kitchens, and balconies.

Class 5 – Heavy Traffic:

Commercial and institutional floors subjected to heavy traffic.

What are “rectified” tiles?

All natural tiles vary slightly between production runs. Sizes change between “batches” and this means that mixing & matching different production batches is seldom possible. “Rectified” tiles are deliberately made over-size, and are then cut on a diamond saw at the factory to a common caliper.

Our manufactured tiles are not rectified but we have a range of imported tiles that are rectified.

Is there a difference between wall and floor tiles?

Wall tiles (because they are not intended to be load bearing) are typically thinner, lighter and softer than floor tiles, and wall tile glazes are not designed to handle abrasion from foot traffic. Increasingly, floor tiles are being applied to walls and this is no problem so long as the walls are strong enough to support their weight and proper ceramic tile installation methods are used. However, it is not recommended using wall tiles in floor applications.

Are breakages common?

It is not unusual to have 2% – 3% of the tiles broken to some degree (e.g. chipped edges). Any amount up to 10% is still considered acceptable. These damaged tiles can be used for the cuts you will need to make. If breakages are above 10%, we would ask you to take pictures and make a claim within 10 days of buying the tiles.

How many tiles do I need?

The area to be tiled needs to be carefully measured to establish how many square feet or meters are involved. This can be done by your architect, builder or your tiler.

You can use our very handy Tile Calculator to work out an approximation, or check results.

Note that there is always a degree of wastage resulting from the cuts required to achieve your tile layout. The contingency allowance for wastage is best estimated by your tiler, but is typically between +5% and +15%, depending on the tiles being used and the complexity of the particular design and layout. Also, consider that it is always wise to keep several spare tiles just in case replacements are required at a later date.

Why should I use tile adhesive or grout instead of cement in tiling?

If you use regular cement or mortar to lay tile, in the long term the tiles will eventually come loose and your grout will crack as well. Tile adhesive is designed specifically to bond tiles to a subfloor. It may be a little more expensive up front, but you will save the cost and hassle of having to buy new tiles and retile your floor at a later date.


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