Ardoise-Slate: The Prestigious Roofing Material of Europe
Ardoise is the French term for a natural stone which geologists denominate as "Slate", or "Schiefer" in German. Slate roofs form an attractive prestigious roof covering whose durability has been proved over hundreds of years of use in Europe. This experience guarantees an attractive long lasting roof covering.
Slate is a quarried natural stratified stone which is hewn into thin plates of 5 to 7mm in thickness. Conventional slate roofing systems are formed from two overlapping layers laid with wide end laps. As a result, the system requires a considerable number of expensive slates per m² in order to form a finished roof. For this reason, asphalt shingles have been developed as the economic and popular imitation of the slate roof finish.
The worldwide sales of roofs covered with slates in 2003 were 30,000 mil m²; 92% of which were in Europe, 5% in the USA and 3% in the rest of the World. The European demand for slates is highest in France, followed by Spain, Germany and Great Britain, with the overall sales demand for slates increasing by 3% per annum.