Re: Liberty Mutual plans major Boston expansion
The toilet core of the existing building was just gutted and rebuilt for big bucks, and modernized onto new stacks. Used to all be on the old 1937 and 57 risers.
Once the new is complete and everone moves over, my understanding is that the existing headquarters office space will/may be gutted (at least floors 3-10 as the cafeteria on 2 was just redone.)
New vertical transportation may be more along the lines of brining the stairs up to modern code. I'd assume the 2 elevator cores (7 cars total existing) would remain.