How to Vent—Details of Steep Slope Vented Roof Design with Structural Insulated Panels

This article discusses how vented structural insulated panels (SIPs) can be applied to a steep-slope roof assembly and discusses design considerations for this type of roof assembly. If designed correctly, venting a compact steep-slope roof assembly can limit the risk for ice dams and moisture accumulation within the roofing system. Vented SIP products consist of insulation, a ventilation layer, and sheathing, and can be fastened to a roof structure to provide a substrate for the primary cladding attachment. Designers must consider attachment of the SIPs, performance of the insulation, the size of inlets and the ventilation plane, and transitions to other systems to maintain continuous ventilation without bulk water intrusion.