What type of decks are considered nailable?

The correct answer identifies the types of decks that are considered nailable, which is a critical aspect in roofing applications. A steel deck, although it is primarily a metal component, is often used with certain fastening techniques that allow for nailing into its edges or using suitable attachment methods. Lightweight insulating concrete, on the other hand, is designed specifically to support roofing materials and is often nailable due to its composition and density that allows fasteners to be effectively driven into it without risking damage to the substrate.

Understanding that nailability is essential for installing roofing systems securely, helps emphasize the importance of choosing the right deck material for specific roofing applications. The combination of these two types, therefore, is significant as it contributes to effective roofing installation practices.

Other options mention combinations that may include substrates primarily not suitable for nailing, or materials that require different mechanical fastening methods, which do not support nailing as effectively as the combination of steel deck and lightweight insulating concrete.