It is a glass wool blanket faced with aluminium foil on one side with 5cm flaps along the edges. It is used for the external thermal insulation of ventilating and air conditioning ducts.
Before the boards are applied, duct surfaces to be used are cleaned to make sure the surface is free from dust and grease. Special self adhesive fixing pins offer fast and easy application. How the blankets are cut depends on the shape of the duct. For the rectangular shaped duct system the blanket length to be cut should be determined as follows: The external perimeter of the duct + (8 x blanket thickness) + 5 cm. For the cylindrical shaped duct system the blanket length to be cut should determined as follows: The external perimeter of the duct + (2 x blanket thickness) + 5 cm. The 5 cm flap provides the cover of the longitudinal joints after the Glass wool is removed from aluminium foil. After the blankets are cut, special self adhesive pins are (5-6 pins per m2) fixed on the duct system. Then the blankets are impaled over the pins. Blankets are held in position by retaining washers. The flap on the materials is then fixed by adhering, stapling or self adhesive aluminium foil tape.