Our DIY Building Plans call out various roof venting elements:
- Bird Block with Screened Vent Holes between the rafters at the soffit
- Rafter Baffles under the roof CDX plywood
- Ridge Vent along the top of the roof
However, the drawings show the top of the 1/2" CDX Ply in contact with the Ridge Beam all along top corners on both side, preventing air from venting out between the rafters and up to the Ridge Vent.
The simple solution is to open an air passageway from under the CDX plywood over the corner of the Ridge Beam.
- At the top of each CDX sheet, cut four channels 1" wide from the top of the CDX down past the Ridge Beam top edge by about 1"-2"; cut two channels between each rafter.
- Alternately, you could use a router to plunge-cut a 1" channel that runs 1"-2" below and 1"-2" above the Ridge Beam corner.
This will allow the air to flow up 1/2" to the roof underlayment, then over the Ridge Beam top corners, and then on up to the Roof Ridge Vent.
We hope this information is helpful.