What are encaustic tiles?

Encaustic tiles are ceramic tiles which have a pattern on the surface. That pattern is not a product of glaze but of different colours of clay.

What is Grout?

Grout is a construction material that can be used to fill voids and seal joints (such as those between tiles). It is generally made up of water, cement, sand. It is applied as a thick emulsion and hardens over time. When mixed and applied correctly it creates a waterproof seal.

Tiling grout is cement based and comes in sanded or unsanded varieties. Sanded contains finely ground silica sand. Unsanded is finer. They can be enhanced by polymers or latex.

Sanded tile grout is cheaper but should not be used when there is a risk of the sand scratching the tile surface, for example glass and certain porcelains.

Grout sealer is a water-based or solvent based sealant applied over dried grout that resists water, oil or acid based contaminants.

PEI Ratings for Tiles

Tiles are classified under the Porcelain Enamel Institute (PEI) ratings system for suitability for fixing in a particular area. PEI Class III is for residential light to moderate traffic. PEI Class IV are for residential floors, moderate traffic areas like bathrooms, halls, kitchens and conservatories. Class V are for all residential floors and medium traffic commercial areas.

Moisture Absorption Rating for Tiles

The American National Standards Institute (ANSI) has developed a rating for moisture absorption for tiles. If moisture penetration is too high, some tiles may crack. Tiles with W.A. Ratings of 0.5% or less are regarded as impervious. 0.5% to 3% is regarded as vitreous.