Terracotta roof tiles: types, performance and installation

Clay tiles: a sustainable choice for roofing

The terracotta tile is valued for its thermal and acoustic insulation, its weather resistance, and its versatile aesthetic. This guide aims to provide a technical and practical overview of the use of clay roof tiles in modern construction. On this page you will find:

• A presentation of the advantages of terracotta tiles
• The list of different types of clay tiles
• Explanations of manufacturing methods
• A summary of the main standards and certifications existing in France and Europe
• Links to trusted companies

Advantages of clay tiles

Thermal and acoustic insulation

Terracotta tiles offer excellent properties.thermal insulationhelping to maintain a stable indoor temperature in buildings, regardless of external weather conditions. In summer, it helps keep the interior cool. In winter, it helps retain heat. Acoustically, the density and mass of the terracotta tile allow it to effectively absorb noise.

Weather resistance

Terracotta is particularly resistant to various weather conditions, including severe weather such as hailThe strength of clay tiles allows them to withstand impacts without cracking or breaking, making them an ideal choice in areas prone to this type of weather phenomenon. Its durability is also enhanced against strong wind, rain, and freeze-thaw cycles.

Appearence

One of the main advantages of clay tiles is their aesthetic appeal. Available in a variety of shapes, sizes, and colors, they can complement many architectural styles, from traditional to modern. The tile's natural color, which can range from red and orange-brown to gray, gives it a warm and welcoming appearance. Its appearance can also improve over time, gaining character as it ages.

The different types of terracotta tiles

Mechanical tiles (small and large mold)

Small mold : this interlocking tile is small in size, which gives the frame a certain lightness. It is often favored in the north of France for its elegance, which is reminiscent of the flat tile.

Large mold : The large-mould clay tile is either slightly curved or strongly curved. It offers an economical advantage due to its large size. It is commonly found in the Southwest and Auvergne-Rhône-Alpes, with bright or pastel shades along the Atlantic coast.

Flat tile

Flat clay tiles are renowned for their resistance to weathering. They are suitable for complex roofs and steep slopes. They are available in rectangular or scalloped shapes (with rounded ends).

Canal tile

The terracotta canal tile, emblematic of the South of France, promotes optimal water flow, lending itself well to low-sloped roofs and Mediterranean climates where rains can be abundant and sudden.

Mechanical regional tiles

These tiles come in regional styles such as the Southern, Roman, and Provençal tiles. The highly curved tile, with its pronounced curvature, is particularly suited to regions prone to heavy rainfall, as it facilitates water runoff. The slightly curved tile, with its softer profile, is suitable for roofs requiring a more subtle aesthetic while still offering good resistance to the elements.

How are terracotta tiles made?

Clay tile manufacturing is a process that combines tradition and modern technology. Here's a simplified summary of the six main stages of the process:

1. Clay extraction : clay, the raw material for terracotta tiles, is extracted from quarries.
2. Transport and preparation : Once extracted, the clay is transported to the factory where it undergoes initial processing. It is ground and mixed with water to obtain the desired consistency.
3. Casting : The mixed clay is then formed into a long ribbon through an extrusion process. This ribbon of clay is cut and molded to form tiles of various sizes.
4. Coloring : In some cases, mineral pigments are added to color the tiles. This allows for a diverse range of shades that can adapt to the aesthetics of different regions or architectural preferences.
5. Drying : The molded tiles are dried to remove excess moisture. This process is essential to ensure the dimensional stability of the tiles.
6. Cook time : The dried tiles are then fired in kilns. Firing takes place at temperatures of around 1000°C, which gives the tiles their durability and strength.

Towards more responsible production methods

To reduce CO2 emissions, manufacturers are increasingly turning to renewable energy sources such as biogas or photovoltaic electricity. Hot air from the kiln cooling zones is recovered and reused in the dryers, thus optimizing energy consumption. Thanks to these innovative production methods and the use of renewable energy, CO2 emissions from clay tile factories can be significantly reduced.

Certifications and standards for clay tiles

Update on the regulatory framework

Flat clay tiles must comply with a regulatory framework that covers the entire product lifecycle, from manufacturing to installation. Fixing rules, procurement procedures, and the management of specific points are among the information sequenced to ensure tile compliance. This framework aims to standardize processes and guarantee consistent quality for flat tiles.

NF Certification

NF certification The NF certification is awarded to terracotta tiles that meet rigorous quality standards and attests to the conformity of the products to current standards as well as to additional specifications that correspond to user needs. NF-certified products offer guarantees of quality and performance and allow them to stand out in the market. 

In France, 61% of consumers prefer to purchase products bearing the NF mark, highlighting the importance of this certification for clay tile manufacturers. NF certification also guarantees the suitability of tiles for traditional roofing installations in France and includes a specific option for their use at altitudes above 900 meters. The process for obtaining NF certification includes several steps: an admissibility study, trials and tests, an on-site audit, the audit report, the certification itself, and finally, regular monitoring.

HEQ certification

High Environmental Quality (HQE) HQE is a certification chosen by construction professionals for healthy and comfortable buildings. The HQE approach is based on an environmental management system for the project and takes into account environmental and health concerns. It applies to the entire life cycle of the building and includes a multi-criteria approach based on 14 objectives, such as eco-construction, eco-management, comfort, and health. Construction products, such as clay roof tiles, can contribute significantly to these objectives.

CE marking

CE marking is a key indicator of product compliance with all harmonized European directives. These directives are legislative texts adopted by the Member States of the European Union and aim to regulate essential requirements in the areas of health, safety, consumer protection, and the environment. 

The CE marking indicates that the clay tile complies with all European Union procedures concerning product conformity.