9. Ventilation of the underside of the roofing

Ventilation of the underside of the tiles and their supports must be ensured. This ventilation is essential to ensure the long-term preservation of the tiles and their wood supports.

The space to be ventilated under the roof consists of :

• or through the volume of the attic if it is not occupied and the roof has no screen;

• or by the air space between the underside of the roof and its support, and the upper surface of the insulation or screen under the slope.

In addition, when installing a screen, the underside must also be ventilated.

Ventilation is provided by eaves and ridge vents connected to the exterior. Depending on the configuration of the roof, the total cross-sections of these ventilation openings are shown in the...