Housing is the mirror of social, cultural and wealth patterns of the era in which it was built. As lifestyle patterns change, houses become less and less able to meet current demands. Rising consumer wealth means families have more possessions, which necessitate larger rooms and closets. Dual-income families mean more appliances and conveniences. In other words, as housing ages, physical deterioration is accompanied by lifestyle obsolescence.
Additionally, as housing ages it becomes less and less attractive to succeeding owners because of its inherent limitations and its continuing need for extensive and expensive updating to enable it to compete with other housing options. In the past, urban renewal was largely accomplished by fires or other natural phenomena which caused houses, neighborhoods or even whole cities to be redeveloped and replaced. Now that these events are largely controlled by science and technology and better municipal services this organic revitalization process has been largely halted. In its place developed a pervasive migration pattern from older urban to newer exurban housing that better met evolving lifestyle requirements – a pattern greatly aided by improved transportation and road networks in the 50s, 60s and 70s.
Because housing is largely built in neighborhoods in the same approximate time frame, as the houses age so do the neighborhoods themselves. This leads to a reduction of property tax revenues with a rising demand for services as the neighborhood inhabitants themselves age and generally become less affluent with each property transfer. Essentially, housing has a life cycle: 0-25 years home improvement, minor replacement an light remodeling; 25-50 years, major improvement, systems replacement and remodeling; 50+ whole house renovation or replacement.