Underfloor heating: how to choose the most suitable tiles

Underfloor heating, also known as radiant panel heating or a radiant underfloor system, is an effective solution that is becoming increasingly popular for modern homes, thanks to the energy efficiency and comfort it offers. The system is based on a coil installed under the floor, through which hot water circulates at a temperature of between 25 and 40 degrees, evenly spreading heat throughout the room. Although these radiant panels can also be installed in the walls or ceiling, the underfloor solution remains the most efficient and widely used, so it is essential to choose the right tiles to ensure maximum performance and optimal thermal comfort.

How to choose the best tile for underfloor heating

The material for use with a radiant panel heating system must be chosen carefully from the various options available on the market. Parquet, a popular choice for its natural warmth, can only be used in a slender, stratified version, because solid wood is subject to thermal expansion, which could have a negative impact on stability. Natural stone materials such as marble and granite, despite their good thermal conductivity, need to be thick, impacting their overall efficiency.

Modern porcelain stoneware solutions are the ideal choice, combining outstanding technical properties with versatility in terms of style. With excellent heat resistance and reduced thickness, porcelain stoneware tiles ensure efficient heat transmission, while maintaining impressive stability to temperature changes. A further advantage of porcelain stoneware is its ability to faithfully mimic the appearance of other materials, so that the desired aesthetic effect can be obtained without impacting technical performance.

The creation of an efficient radiant heating system requires an in-depth understanding of the properties of the materials used and how they interact with heat. These technical aspects determine not only the energy efficiency of the system, but also the thermal comfort of the areas it is installed in, and the duration of the investment.

Porcelain stoneware: superior thermal performance

The efficiency of a radiant heat system is closely linked to the capacity of the floor to transmit heat. The thermal resistance of the covering material must not, by law, exceed 0.15 m²K/W, so it is essential to take this parameter into account when choosing the most suitable tiles. The thermal conductivity and thickness of the material are the two key factors that determine this resistance.

Stone-effect porcelain floor tiles for underfloor heating in a minimalist living room. — Omnia Tivoli Ivory

The compact structure of porcelain stoneware, derived from a process of pressing and firing at high temperatures, guarantees an optimal combination of two essential characteristics: a high thermal conductivity coefficient and the possibility to produce tiles with a reduced thickness, thus ensuring a rapid, efficient heat exchange. This optimal combination enables a rapid, even spread of heat throughout the setting, overcoming the limits of other materials such as marble or granite, which, although they have good conductivity, require greater thicknesses, which negatively impacts efficiency.

Another decisive aspect when it comes to choosing tiles is how they react to temperature changes in the system, which operates at between 25 and 40 degrees. A distinctive feature of porcelain stoneware is its thermal expansion of virtually zero, which means it is practically unaffected by changes in temperature. This characteristic is essential to keep the flooring in prime condition, avoiding the problems that typically arise with materials with high thermal expansion, such as cracking or detachment, which could damage both the appearance and the functioning of the entire heating system.

Wood-effect floor tiles with underfloor heating in modern bathroom. — Journey Watercolor

The right thickness of tiles for underfloor heating

Tile thickness is a key element to guarantee the efficiency of underfloor heating. The thinner the layer of material the heat has to pass through, the quicker it will heat the room. This is what makes thin tiles an excellent solution for radiant heat systems.

Thinner tiles offer a number of practical advantages: as well as better thermal conductivity, they allow for lighter flooring overall, making them ideal for both new builds and renovations. When choosing tile thickness, it is important to take account of the technical specifications of the product and how it is to be used, and to follow the manufacturer’s indications in order to guarantee maximum efficiency and durability of the heating system.

It is important to note that the reduction in thickness has no impact on the resistance of the material: even the thinnest porcelain stoneware tiles guarantee adequate impact resistance for residential and commercial applications in light traffic areas, as well as adequate tread and thermal shock resistance, ensuring excellent duration and consistently high performance for the heating system.

Find your ideal flooring with Match App

Need help choosing the right tiles for your underfloor heating system? Use the Match App flooring visualizer to guide you towards the ideal choice, combining the technical specifications required with the design you’re looking for.