Do fasteners matter? Accepted practices for thermal performance evaluations negate fasteners. But with the advent of exterior insulation, fasteners and cladding attachment systems now serve as the primary bridging elements within typical clear fields. These components inherently disrupt the insulation layer, providing intermittent continuity with sheathing and studs. Furthermore, the ‘cladding attachment system’ has essentially morphed into the ‘cladding fastening system’ while also achieving de facto exclusion from thermal calculations. In other words, prescriptive R-values and alternative U-factors did not account for the ill effects of these thermal bridges. What ensued was a decade of under-achieving walls where effective R-vales were only marginally better than conventional framed assemblies. In this presentation, I offer clarity on the effects of fasteners and cladding attachment systems that vary in both material and form. My findings show that fasteners do matter and that certain fasteners warrant inclusion for thermal calculations and code compliance.

Presented by various experts on behalf of DuPont Performance Building Solutions.