On Oct 15, 11:36 am, wrote:
I'm adding your story to my long list of reasons why I hate cathedral
ceilings.


Which makes no sense, because you can screw up construction on
anything and it has nothing to do with it being a cathedral ceiling.

Regarding the OP's problem, I agree with those that say there is far
too little info here to know who is at fault. One key is that it
appears the contractor in question was only responsible for framing.
There should have been a drawing done to get the building permit.
Who did this drawing and what did it show? What does the contract
say? I someon else did the drawing and the contractor only framed it
as shown, then I'd say he is not legally responsible. However, an
experienced framer that has been doing this type of work should have
spotted it and said something.

As someone else pointed out, with a cathedral ceiling, ventilation is
one of the things that is always considered upfront. Typically, you
spec baffles to be placed under the sheathing to keep a couple inch
channel free of insulation from soffits to peak. And then,
obviously, you need some means for it to exit there, usually a ridge
vent.

It sounds to me like this whole job may have been poorly defined and
it may be difficult to pin down any one person as responsible.