I was making a model of a house to help design a renovation and in my measuring I discovered that the center load bearing wall on the first floor was not centered over the load bearing beam and columns in the basement below by a difference of about 8". The cross section shown below is to scale and is the entire house; it's a 20' x 40' rectangle in plan. First floor joists are 2x8's and ceiling joists are 2x6's. Upper space is finished and is an occupied bedroom. It’s in the state of Wisconsin, USA. House was built in 1930, every framing member is douglas fir.
I found this to be so strange. Is there any reason to do this other than lending asymmetry to the floor plan? Is this legit? This seems like an unstable arrangement in the long term.