replacing sagging floor joists- Advice anyone?
I have a fairly large farm house in which every room, on the first floor, suffers from sagging floors. The span for each room varies from 12' to 16'. Regardless of span, all floors have 2x8 joists-true 2x8 joists and made out of oak and chestnut but obviously insufficient. I've thought about lvls, flitch beams, and have actually put steel I-beams with jack posts under a couple already (as a temporary fix until I find a permanent solution). One of the problems with the already too small joists is that each one is mortised into an oak beam. So, at the ends, the joists are actually 2x3. These joists are over 100 yrs. old and deflection is so bad I'm thinking about getting them out of there. My idea is to replace them with new 2x12s or 2x10s (depending on the room) which will be tied into another 2x12 which I bolt into the original oak beam (like a ledger board). I figure this will allow me to level the floors as well. Since the beams are 6x8 I plan to screw a joist shelf onto the bottom of the ledger boards and then use joist hangers to tie in the new joists to the ledger. My 3 and 5 year old kids love the spring action in the floors but I'm sick of my desk drawers coming open on their own. Is this solution a solution?