[ta1243]

If the town population doesn't grow (100 deaths each year, 100 births, equal immigration and emigration) then new houses aren't needed. Sure you have kids needing a new home, but then your parents die, freeing up an old home

The reason we need more housing is

1) Concentration of living in certain areas more than in the past

2) Smaller households (more common to have a family unit of 2 parents and 3 kids being divorced, with both parents wanting a house large enough to keep the kids on alternating weekends)

3) Increasing population (both from longer lives, more births, and net immigration)