I’ve got a finished attic project that involves a couple variables.

The existing (somewhat complex) roof is a 12/12 pitch or steeper framed with 2×8’s 16″ o.c..  The house is asphalt shingled and is located in northern Illinois.

The entire roof is ridge vented today.  Rough interior peaks range from 9 to 12 feet.  Only certain middle (gabled) sections of the attic will be finished, resulting in the finished spaces being surrounded by cold/hot attic. 

The design calls for 4′ knee walls, cathedral ceilings and small dropped ceilings in the taller sections.

Not to encourage flames, but I have been 80% convinced by the new recommendations to seal cathedral ceilings when insulating instead of venting.  Even though this will require special efforts to maintain seals around the knee walls, etc..  Given the shallow 2×8 rafters, I’m guessing I’ll be lucky to get R-21 if I try to keep the vent space anyway.

My question is this: should I remove the ridge vent over the new cathedral ceilings?My assumption has been that unless I take this step, the chimney effect of the open top vent might compromise my sealing efforts. (no pun intended)

All thoughts welcome.  Thanks.