Straddling rafter with roof vent

[Stanek]

I have a 5/12 pitch roof and am putting a new room under it that is going to be vaulted. I'll put sheetrock right onto the underside of the rafters and will use a rigid insulation to get my R30. I plan on leaving a gap above the insulation and already have eave vents but need to get venting at the top end of each "cell" space between the rafters to get the air flow. I'm thinking of using a ridge vent but due to another roof line that intersects this ridge I thought I would just do regular round vents between each rafter. Then I thought, what if I place a little bigger vents over the top of the rafter thus splitting a vent between two cells and thereby cutting in half the number of vents on my roof? If I still keep the 1 to 150 ratio would this be ok?

[shinstr]

Ridge vents would be easier, however they must stop 2' short of any transition. For this remaining area, you can drill holes in the rafters (NOT TOO BIG..less than 1/4 the thickness of the rafter i beleive is the rule...someone correct me if I'm wrong...and NOT in the bottom 1/3) to transfer the exhaust from one "cell" to another that is vented.

Good Luck!

[Ed Imeduc]

Then I thought, what if I place a little bigger vents over the top of the rafter thus splitting a vent between two cells and thereby cutting in half the number of vents on my roof? If I still keep the 1 to 150 ratio would this be ok?

Sure sounds good to me all the way

ED :D