A couple of years ago a raccoon ripped open an eave vent in a cathedral
ceiling next to the chimney and just above a casement window and moved
in. It took awhile for me to catch on. I eventually caught and
relocated several raccoons and had the vent repaired. I sleep just
beneath that cathedral ceiling in the loft. B4 the repair I was able to
sit in the casement window and hold a digital camera in the hole and
snap a few pictures. It appeared that any insulation in there had been
pushed back. I'm guessing fiberglass batts. The repair was combined
with re-siding several months later, and the insulation was never
replaced (my bad). I can confirm this in both winter and summer by
reaching up and feeling the temp differential in that one 16"? run in
the ceiling. I can touch the ceiling from the loft. I'm thinking about
cutting a wide hole through the ceiling sheetrock and blowing some
cellulose into that run. How doable is this (inside the house), and
what alternatives are there?

p.s. there is some chance that I may reroof in the near future (hail
damage). This roof is 2 1/2 stories up. Would it be easier to do this
repair then? Of course the roofers in this area are swamped and want to
do the roof and run to the next job.