“Typical single family home foundations consist of reinforced concrete, but reinforced concrete is a poor choice for a long lifespan building due to its susceptibility to corrosion.”
The rebar that makes modern concrete strong is the same rebar that rusts and cracks it apart within a century. The Pantheon has stood for 1,900 years on unreinforced concrete. Builders know this. Nobody pays for a house that outlives the mortgage.