Wall insulation detail, is this OK

[Keith]

I am opening a NE facing brick veneer over 2x4 wall in southeast Virginia to accept a larger series of windows. I plan to do the following on the interior:

Insulate the bays in the 2x4 wall with faced R13 Cover wall with 1/2 7 layer cabinet grade plywood( gotta good deal ) screwed every 6 inches or so for rack resistance ( paranoia ) layer 1/2 inch of rigid foam, tape seams

1/2 drywall over that.

Questions: It looks like I will have 2 vapor barriors, will the plywood rot? Should I even worry about the foam? It will only add R3 over the studs Can I screw through the 1/2 inch drywall through the foam into the plywood substrate with no worries about moving seams later.

Any other reccomendations?

[tbasc]

The foam seems an unneeded complication. If the sheathing on the cavity face of the studs is acceptable, gypsum board should be o.k in most situations. As I understand it, the issue with large window openings includes anchorage of the frame to the foundation. Local codes should note wind speed to be used for design. TB