My house was built in 1942 so I may be hosed.
But, consider also that (in 42) they built houses to last either 80 years (no plywood, tarpaper and composite glued waferboard and "skinny" 2x4's!) or they built them to only 3 years (to make do for emergency barracks for transients during the war!)
So, remeber your house is made BEFORE the cheap post-war Levittown mass produced pieces of light-weight copy-cats..