Originally used only in Mediterranean regions and partly in the South-West, canal tiles are now used in all regions. This has meant imposing specific rules for the installation of these materials, depending on the climatic zones in which they are used.
According to DTU 40.22 (
NF P31-201
and
NF P31-202
1997 + amendments A1 to A4) – As with all roofing materials, clay roofing tiles can be used anywhere in mainland France, from north to south and from west to east.
However, the practical use corresponds to regional habits (mainly in the West, south of the Loire, Centre, Atlantic and Mediterranean regions). Use in mountain climates is not covered by DTU 40.22. In fact, this type of climate, conventionally defined by an altitude of over 900 m, is not well suited to clay roofing materials, due to frost phenomena which, by alternating and repeating freeze/thaw cycles, end up destroying the tiles.