This handbook provides an overview of the climate-zone-specific best practices for designing and installing compact vented roof assemblies for conditioned attics.

Because insulation in a compact vented roof is installed directly beneath the roof sheathing, little space remains for drying if water vapor accumulates. Ventilation channels above the insulation help remove incidental moisture and reduce the risk of condensation within the assembly. Ventilation also supports shingle durability and helps moderate heat buildup at the roof surface. When done correctly, vented roofs for cathedralized attics deliver efficiency, comfort, and durability. This guide can help contractors nail those details.