Forming eaves vents with I-joists
My house’s roof is going to be a shed roof formed with 14″ i-joists. They’ll sit on beveled plates on the attic floor. At the top and bottom, there will be LSL blocking angled perpendicular to the plane of the roof. The blocking has to be full height, and can only be v-cut in the center third for ventilation.
The attic floor will be covered with around 18″ of insulation, reduced at the low end by the height of the joists. I would like to form a ventilation channel using the flanges of the i-joists, which gives a 1.25″ deep channel. For adequate ventilation area, the depth of the v-cut needs to be much deeper than the channel. I’m wondering how best to connect the v-cut to the ventilation channel.
Because the blocking angles away from the house (it’s sitting on a beveled plate), I was thinking that I could form a triangular ventilation space behind it that would steer air up to the ventilation channel. I would nail a backer block to the joist webs, and install thin plywood vertically, and have it meet the ventilation channel along the roof.
Does this sound like a good solution? Is there a better way?
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