The studs at the rear right of the barn in the area that will become the workshop had a fairly significant amount of rot. These will be replaced prior to building the new floor and the "services" wall. The cabling is the barn power feeder from the house.
Closeup of stud showing carpenter ant damage
The rear left corner support post in the barn had very significant decay, to the point that it was not supporting any load. The load for this corner - and hence the load transferred down from the roof was being supported by the surrounding studs, some of which had also decayed. This required immediate attention before the new sub-floor surface could be installed.