Overview
Cladding materials are generally attached directly to the structural framework or components of a building (e.g., studs, girts, etc.). However, where FPIS is used on the exterior of a building, there is opportunity to not only reduce heat loss through thermal bridging of framing members but also an opportunity to reduce thermal bridging through cladding connections. Properly specified cladding connections (fasteners) through foam sheathing can dramatically reduce heat loss thermally inefficient methods such as Z-furring extending continuously through one or more insulation layers. Instead, fasteners can be specified to penetrate an exterior continuous insulation layer allowing furring or siding to be placed directly over the exterior insulation. The fastener type and schedule will depend on cladding weight, method of attachment (furring or direct), and type of structural substrate (steel framing, wood framing, or wood structural panel fastening base). Such provisions are included in modern model building codes (reference IBC and IRC 2015/2018 provisions).
For additional guidance in fastening through FPIS, refer to:
- Technical Evaluation Report: Attachment of Exterior Wall Coverings Through Foam Plastic Insulating Sheathing (FPIS) to Wood Wall Framing
- Research Report: Attachment of Exterior Wall Coverings Through Foam Plastic Insulating Sheathing (FPIS) to Wood or Steel Wall Framing
NEXT STEPS: Go on to STEP 5.