2007 CBC - Attic Ventilation Questions

I have a few questions regarding attic ventilation and the 2007 CBC (1203.2, etc.) that came up during a discussion:

1) Can someone use both 1/150 and 1/300 to determine the attic ventilation required? Someone would like to use 1/150 at the attic space over the conditioned area and 1/300 at the space over the unconditioned areas. However, the spaces intercommunicate. If this is permitted, would the vapor retarder be required (1/300 applied at unconditioned space)? Any thoughts are much appreciated.

2) Someone stated that eave vents cannot be placed at shear wall locations or over windows. True? If so, where does it state this in the code?
Original Post
Annette
Another bit of info for your #2 above;
Eave vents over shear walls can be a structural problem for engineered applications. The Engineer must determine the shear load and blocking capacity to allow a completely open vent rafter bay or drilled hole size and strength for the remaining material in the block to transfer shear loads.
If conventional construction then there is no direct code provision prohibiting eave vents over shear walls. Would recommend that the eave blocks be full if possible over short higher loaded walls.
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