[wrp]

My impression is the institution of boarding houses died out in the 1940s (in the USA).

In researching family history, I was surprised to discover how frequently a nuclear family would have various relatives living with them. This was up through the 1930s. It seems that American ideas of desirable personal space changed significantly around the 1940s.

[PaulHoule]

People had larger nuclear families and a lesser standard of living.

My dad was born in 1942 and was one of 5 brothers and 1 sister, they grew up on one side of a big old walk-up apartment building odin the French-Canadian district of Manchester, NH. The brothers shared a bed and my dad was resentful that he got hand-me-down shoes from his brothers.