Which type of membrane fastening is fully adhered and commonly used for SBS?

The choice of "fully adhered" as the correct answer highlights a specific method of installation for roofing membranes, particularly those made of Styrene-Butadiene-Styrene (SBS) modified bitumen. In a fully adhered system, the membrane is glued or bonded directly to the substrate using adhesives, which ensures a secure attachment and minimizes issues related to wind uplift. This method is particularly advantageous because it can enhance the waterproofing capabilities of the roof system, improve performance under various weather conditions, and reduce the likelihood of membrane damage from mechanical fastening systems.

The use of fully adhered membranes with SBS is also significant because this type of roofing material is designed to provide flexibility and resistance to thermal cycling. The adhesive promotes a seamless application that can help prevent water infiltration and contributes to the longevity of the roof assembly.

Options like mechanically fastened and loose-laid ballast describe alternative methods of installation that do not involve complete adhesion of the membrane to the substrate. Mechanically fastened systems rely on physical fasteners to secure the membrane, while loose-laid ballast systems use materials like gravel or pavers to weigh down the membrane without adhesive. Single-ply membrane is a broader category that doesn't specifically indicate the fastening method used. Thus, fully adhered is the most accurate