Somewhat unique cathedral ceiling question

I have a 12/12 pitch cathedral ceiling.  Rafters are 12″ I joist with 10″ open cell spray foam in them as well as ventilation baffles under the roof sheathing.  At… I have a 12/12 pitch cathedral ceiling.  Rafters are 12″ I joist with 10″ open cell spray foam in them as well as ventilation baffles under the roof sheathing.  At…Read MoreGreenBuildingAdvisor