Cellulose insulation in new saltbox roof (Zone 5a coastal)
In order to minimize Treated Floor Area, and to simply enclose a proposed house with less volume on the second floor, I plan to use a saltbox roof. Are there any concerns with transitioning from dense pack in the unvented slopes to loose fill above the flat ceilings? Or should there be a vent channel in the slopes only that rides up higher than the depth of the loose fill?
Also, I am not planning to use a ridge beam, so collar ties of some sort will be needed for a stick-framed roof. If their ends penetrate into the roof member cavity, I am concerned about continuity of the thermal barrier. Perhaps a simple truss will keep the bottom member outside the insulation cavity, then use I-joists (to maximize depth) for the sloped ceilings?
GBA Detail Library
A collection of one thousand construction details organized by climate and house part