The roof spaces consists of a conventional framework made up of angled rafters and horizontal purlins. The installation will consist of placing a first layer of insulation between rafters, completed with a second layer perpendicularly staggered in order to comply with regulatory demands (R = 5 m2.K/W).
If the finish is a gypsum board on a metal framework :
Screw the facing to the previously installed metal framework.
Store rolls and batts in their original packaging, protected from rain and direct sunlight.
Cut the insulation to the required width between supports, with an excess of 2 cm, and place the insulation under gentle compression ("spring effect") to ensure perfect contact with the uprights.
To ensure continuous insulation, take special care when sealing the joints between walls (wall / floor / slope) and checking that the strips are in perfect contact.
Ensure the maximum seal of the insulation by installing an offset, continuous vapour barrier on the inside (hot) and a roof-boarding screen that is pervious to water vapour on the outside (cold).
Install a finishing facing with maximal fire rating (mandatory).