An intermediate floor, with a light structure made up of wooden joists, separates two volumes, at least one of which is heated. The insulation will consist of filling the spaces between joists with semi-rigid insulation (rolls or batts) or manually deposited fibres.
Two facings are required in this configuration. They are most commonly made up of :
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).