Owned a home for 12 years and foundation is falling apart

[Ray A Delfi]

Hey quick question. I pulled the subfloor up to sister up the joist and get the floor plumb but my contractor just reported that all the wood is deteriorating and falling apart. Is this something my insurance could cover? It’s a two family building built in 1910 and I owned it for 12 years. The contractor is assuming previous insect damage and rot from moisture. Only way to fix it is to reframe the floor and pour concrete around the foundation as the joist hangers are all falling apart and no wood left to bite into.