We have to get a new roof soon for our 1924 colonial in NY. We plan on an unvented attic as per buildingscience.com etc. Part of that will require above roof deck insulation of about 2 inches of rigid polyiso foam boards. I understand that usually the roofer puts the boards on the existing deck then 3/4 plywood on top of that and screws down into the rafters and decking. Due to the added 2.75 inches from the boards and plywood, the eave fascias will have to be replaced. And I guess the trim or fascia by the rake (gable walls) will also have to be replaced or expanded. On the rake I wanted to know if it is big job to raise the fascia and also replace the aluminum trim installed there at the time the house added vinyl siding. Is Is this all fairly simple for a roofer to do?