Suspended & cantilevered joists

I just purchased this (time capsule) house with more than a few unconventional homeowner/handyman specials. This suspended/cantilevered "mezzanine" part of a finished attic space being the biggest head scratcher.


Background: Built 1924 as a summer home, converted to year round in 1943
true 2x4 framing and rafters, 24" OC.
2x8 joists with varied spacing. 17"-22" OC
Timber beams added for aesthetics only in 1961. They appear to be bolted and rodded to the 2x4 roof structure which is above the planking.



This suspended area seems to have been constructed in order to lower the joists to provide more headroom to have a finished room in the attic. It was used as as a bedroom for 30 years. It has (of course) dipped about 1" in the unsupported corner. I believe the joists in this corner are bolted to the timber beam which is suspended from the rafters above the planking.


My question is (in addition to "what the f...?") Any ideas on how to support this without extending the load bearing wall which is, of course) supporting the rest of the joists. Extending the wall would greatly impede the living room space.

Of course, an engineer will be consulted as well, but wanted to see if there were any good ideas milling about the members here. Thank you!

Stair Baluster is not supporting joists in any way. It was just shoved in there for some reason. Not structural.

 

Follow the guidance of your Engineer, not strangers on the Internet. You provided a lot of good pictures but there are still many questions. 1920's construction with non-structural beams and who knows what else really demands an on site inspection.

What's below that unsupported corner? A column under the unsupported corner might be an option but a load path to the ground needs to be worked out. A footer & column in the basement/crawlspace could support a column between the floor and floating corner. Or, you could use a beam to move the load to the outer load bearing walls of the house. Or, the floating corner can be hung from above, with additional rafter strength (maybe collar ties). But all of this will depend on things like where windows are located, how the outer walls are constructed, existing footers... The devil is in the details.

 

Since an engineer is needed to look at this, there's not much reason for us to think about this too hard. But I would just guess that the engineer might suggest jacking it up so its straight... building a temporary wall under it... building a structural truss that would act like a beam. It would cap the beams in photo one, and it would need to sit on the exterior wall on one end and on that outside corner (on the left in your last photo). The outside corner would need to be supported underneath to a footing. Hard to say much more than that when we aren't there in person... like your engineer will be.