Used to have a cedar shake roof, lower ventilation consisted of 1" holes cut into cedar planks where soffits go (what's the proper term?).
They sheeted the roof, installed asphalt shingles with a ridge vent and alum. soffits. Took a look under the soffits, they cut a strip (roughly 2-4" wide) on the outside edge of the cedar planking prior to putting the soffits up. They also stuck 4" pipe to run from the soffit intake, into the attic (sort of a baffle I guess).
Is that 2-4" strip enough to provide the ventilation if they only had 1" holes cut before?