Ceramic tiles are widely regarded as a reliable and durable flooring material in the modern world. While this is true, choosing floor tiles from a store can sometimes lead to selecting slippery or fragile options that cause issues during use. To avoid this, ensure the tiles meet the essential criteria for reliability. So, how to choose floor tiles?
Slip Resistance
Neglecting this parameter can make tile use unsafe. Manufacturers today offer many beautiful but slippery tile series. Polished or lappato-finished tiles have limited applications. For residential and commercial spaces, tiles with sufficient slip resistance are a better choice.
This property is measured using specific coefficients defined by DIN 51130 and DIN 51097 standards and is indicated by the letter R. European standards classify tiles into groups from R9 to R13. The higher the R rating, the better the slip resistance and practicality of the tile. This factor is especially important for areas like kitchens, bathrooms, hallways, children’s rooms, and entry thresholds.
Tile Durability
For tiles, combining wear resistance and strength is key. However, even for floor tiles, several criteria must be considered:
- Surface hardness – Measured on the Mohs scale, this parameter is relevant for glazed tiles and indicates scratch resistance. A rating of at least 5 is recommended.
- Flexural strength – A critical indicator for floor tiles, categorized into three levels (BIb from 16 to 27 N/mm²) according to ISO standards. It measures the tile’s ability to withstand load across different points.
- Chemical resistance – Marked with letters A, B, C, or D, this measures the tile’s ability to maintain its appearance and properties after exposure to various substances. Tiles with an AA rating offer the highest resistance.
- Abrasion resistance – This shows how well a tile withstands wear from abrasive particles. Applicable to unglazed tiles, it is marked as PEI (I-V), with higher Roman numerals indicating better performance.
Tiles for high-traffic public areas should have the highest durability. For residential spaces, the requirements are less strict.
Thermal Resistance
The behavior of tiles under cooling or heating determines their suitability for different environments. Tiles that don’t meet the standards should not be used outdoors. Two key factors to evaluate are:
- Frost resistance – The ability to resist water absorption and subsequent expansion within the tile’s pores at temperatures below 0°C.
- Resistance to temperature fluctuations – Assessed through repeated heating and cooling cycles with a temperature range of at least 100°C. This test evaluates how the tiles will perform outdoors.
Frost-resistant tiles are marked to indicate compliance with EN ISO 10545-12 standards. For indoor heated spaces, frost resistance is less critical.
Porosity
The tile’s ability to absorb water depends on its structure and quality. Higher porosity means lower density. Tiles for high-humidity areas should have a porosity of approximately 3%, while tiles for other rooms can have up to 6%.
Water absorption rates are divided into three groups:
- IIa – 3–6%
- IIb – 6–10%
- III – Over 10%
Tiles in the third group have limited applications and are rarely used for flooring.
Thermal Conductivity
This factor is crucial when installing underfloor heating. Tiles should efficiently transfer heat from the heating elements; otherwise, maintaining a comfortable temperature becomes costly.
Thermal conductivity is denoted by λ, but this parameter isn’t usually listed on the packaging. However, lower porosity generally means higher thermal conductivity.
Tile Dimensions
Tile size depends on room size and interior design preferences. For bathrooms and kitchens in typical apartments, tiles sized 300×300 mm are suitable. For hallways, living rooms, and bedrooms, 600×600 mm tiles are commonly chosen. Diagonally laid large tiles visually expand the space. The proportion of tiles to room dimensions should feel balanced.
Non-standard tile sizes, which have recently gained popularity, can mimic parquet or hardwood planks. These versatile tiles suit all rooms and can be used with underfloor heating. Sizes for such tiles include 600×150 mm or 600×200 mm.
Tile Calibration
Actual tile dimensions often differ slightly from the stated measurements. Manufacturers indicate these variations on the packaging to help buyers choose tiles with a size difference of no more than one calibration step. Larger discrepancies may compromise the quality of installation.
When selecting tiles for indoor use, frost resistance and thermal expansion tolerance are less critical. However, all other criteria remain important, and outdoor tiles must meet all these requirements.