R806.1

Section R806.1 is titled 'Ventilation required' and covers the requirements for providing openings to allow for air circulation within attic and rafter spaces. The areas required to be ventilated, protection of ventilation openings from precipitation entry, size of ventilation openings, a cross-reference to another section of this code which covers cutting, notching, and drilling of framing members, and protection from animal entry is established. The purpose of this section is to prevent excessive mold growth, moisture collection inside the building, and premature degradation of framing members.

The model shows 2 partial roof-ceiling assemblies. The 1st has an attic area which allows air from soffit and mushroom vents to circulate through the attic area. The 2nd has a cathedral ceiling with enclosed rafter spaces, with notches in the rafters to allow air from soffit vents to communicate with the mushroom vent opening.