My 10-yo house has 14 foot ceilings in the bathroom and bedroom. Both have vaulted ceilings finished with SLAM on the interior corners. (Maybe 60 degree joints?) One piece of the SLAM has fallen down entirely, and the others are noticeably loosening at the edges. What is the best way to repair these given the height of the ceilings and the non-square corners? Can I slap some more joint compound up there and smash the SLAM back up? Or do I skip the SLAM entirely and try to finish it neatly without the SLAM? And where the SLAM is merely loosened, can I reattach it using a thin coat of compound?
I've installed plenty of drywall, but this is a step beyond anything I've had to do. Thanks for any advice you can give!