The ceramic versus glass mosaic tile debate, is as old as the rivalry between Melbourne and Sydney. Whilst arguing the superiority of Melbourne or Sydney might be a fool’s errand, taking time to understand the advantages and disadvantages of ceramic and glass tiles could save you from making an expensive mistake.
First, let’s define exactly what we’re talking about…
Ceramic tiles are made from natural and abundant raw materials including clay, sand and minerals. Ceramic pool tiles, are typically porcelain’, which is defined by their very low water absorption rate (≤0.5%) created by higher firing temperatures. Zero water absorption isn’t necessarily a good thing, more on that later.
Glass tiles: The main ingredient of glass is sand, also known as silica. Glass tiles are characterised by their translucency and impervious water absorption rate.
For the sake of this exercise, let’s assume both options are specifically manufactured to be a pool tile’, that is, they are designed to withstand high UV, changing temperatures, and constant contact with the chemicals in swimming pool water. Not to be confused with a regular bathroom or kitchen mosaic, which simply would not last long in the relatively harsh environment of a swimming pool.
Now that we have the basics covered, let’s delve into exactly separates glass and ceramic tiles.
Glass Mosaic Tiles
Ceramic Mosaic Tiles
|Price of tiles||$$$||$$|
|Labour Installation costs||More expensive||Less expensive|
|Bond Strength||Less bond strength||Higher bond strength|
|Cleanability||Equally easy to maintain||Equally easy to maintain|
|Design aesthetic||The translucency of glass compliments water||
Some might say slightly less, but it is very subjective and dependent on the tile
|Longevity||High risk of delamination due to no adhesive bond and/or inappropriate installation technique||High durability|
Ceramic tiles have very low levels of water absorption, and that is a good thing. The reason is, a small amount of water absorption allows for the glue to bond better, no water absorption means less bond strength. This is the reason why glass mosaic tiles require a special more expensive epoxy glue, and if too little glue is applied at installation there is an increased risk the glass tiles will begin to detach. Because glass tiles are made so thin, a tiler might use less glue to avoid it squishing up between the tiles and onto the face. Therefore laying glass tiles is more time-consuming, which is the primary reason why tilers will charge a higher rate per metre to install.
Paul Buckley, National Ceramic Product Manager for Mapei, one of the largest quality adhesive manufacturers offers the following technical advice:
There are many issues that can arise with the laying of glass mosaics:
- The shape of the glass mosaic is concaved on the back side, bevelled on the outer edges of the backside and they are only 3 mm in thickness.
- The 3 mm thickness leads to only a small sized notched trowel being used to spread the adhesive so as not to have adhesive enter the grout joint that in turn would need to be removed prior to grouting taking place.
- The small notched trowel leads to a reduced adhesive contact due to the mosaics being concaved and bevelled at the back.
- When glass mosaics are installed over a membrane there is no absorption into the membrane and no absorption into the glass, this can create a weak bond, it can also prolong the curing of the adhesive thus if they are trafficked to soon detachment can take place, this can be picked up and rectified during the grouting process but sometimes this can be missed and then the only thing holding the mosaic in is the grout in the grout joint.
- The best way for glass mosaics to be laid is using an adhesive that is coloured the same as the desired grout colour, this can be achieved using a latex or even better, is to lay them with a coloured epoxy. However, this method is expensive and therefore most often disregarded.
- Refer to section 2.2.2 “Mosaic Tiles” from the Australia Standard AS 3958.1 for more information.
The main reason why epoxy is more expensive is the labour cost as it is very difficult to work with. One pool tiler we spoke with summed it nicely “Epoxy is sticky, it gets into everything, and if it sets on the face it needs to be removed immediately otherwise it is nearly impossible to remove, which makes laying time-consuming”.
So why choose glass tiles at all? The translucency of glass compliments water and there is a perception that glass tiles will contribute to a more beautiful water appearance. However, a premium ceramic tile that offers colour and/or surface variation will create an equally pleasing look. This in part explains the popularity of Amano, which has a glassy’ aesthetic achieved by clever glaze application during firing, without any of the inherent issues of glass.
The final verdict…
There are distinct differences between glass and ceramic in supply and install price, bond strength and longevity. Whichever tile you decide on, remember a lot depends on the quality of the tile so it is worth researching where the tile was manufactured and purchasing from a trusted supplier.
If this article raises more questions, please do not hesitate to contact us as firstname.lastname@example.org.
Good luck with your decision…