i have a question regarding ventilation in a cathedral ceiling. i recently changed the roof and rafters on an existing house from a 5/12 pitch to a 12/12 pitch roof. the rafters are 2x8 and i plan on using 6 in. r-19 fiberglass kraft backed insulation with the preformed dura vent foam panel to keep the air space open between the roof and insulation. i have installed a ridge vent and soffit vent. the question is, what should i do where the intersecting gable and valley rafters don't allow soffit ventilation through to the jack rafters? would the ridge vent be enough? this intersecting gable does face to the north and would be cooler than the rest of the roof. i thought about holes through the valley rafter but i would lose strength in the valley rafter. i assume that this would not be the best thing to do. if anyone has faced this this situation before please let me know what you did. thanks.

You need to ventlate the hips and valleys, the best way to do this is to drill a 2" hole as high as you can on the rafter, and then add an angled framing anchor.

Or glue and nail a 12" long piece of 1/2" plywood on the uphill side and then drill the hole thru.