What type of insulation is installed above the roof sheathing in the Air-permeable Insulation Method?

In the context of the Air-permeable Insulation Method, air-permeable insulation refers to materials that allow air to pass through them while still providing excellent thermal resistance. This type of insulation is typically used above the roof sheathing to create a more continuous thermal barrier and enhance energy efficiency in a building.

Air-permeable insulation materials, such as fiberglass or cellulose, are designed to maintain their insulating properties while allowing moisture to escape. This characteristic is particularly important because it helps to prevent condensation and subsequent issues like mold and rot that could arise in the roof assembly. By placing this type of insulation above the roof sheathing, it also minimizes the risk of creating a cold roof that can lead to ice damming in colder climates.

In summary, the correct choice is air-permeable insulation because it directly aligns with the principles of the Air-permeable Insulation Method, focusing on moisture management and thermal performance above the roof sheathing.