I have a Cape house built in the mid 60's. The insulation from other parts of the house is Fiberglass but not nearly as thick as R-13. I would guess around R-10 maybe? I cut a small hole in the attic/ceiling and its the same insulation. I have no access to the attic/ceiling but was thinking of cutting a hole to fit through to add insulation throughout the attic. Looking from the outside I only have about 2.5 feet between the top of the window to the peak of the roof. I dont think this would be enough space to insulate. Not to mention the dormered roof I would not be able to get the entire width. I have only gable vents and live in Boston MA where the recommended R value in the attic is R-49.

How do I insulate the attic? Do I need to redo the second floor?