Among the many housing related variables in the AGS library, the year structure built table almost always appears on multi-page demographic reports and is an integral component of analysis in insurance and home repair. Many home repair services are based on franchise areas which should take into consideration the age distribution of the housing units.
The map below shows the dominant regional patterns of two variables – the % of housing older than 50 years, and the % of housing less than 10 years. The map is at the block group level, but using a two mile filter at each block centroid to smooth the results.
In part, the map reflects areas of recent growth – clearly showing the growth over the past decade of the traditional south from Virginia to Texas. Other significant areas of new housing are in the southwest from Tucson to Las Vegas, along the front range of Colorado, Salt Lake City, and the valleys of Washington and Oregon.
The red areas are those where at least 50% of the houses more than fifty years old – primarily across the “rust belt”, the great plains, and the large urban areas of Los Angeles and San Francisco.
One of the popular variables that is derived from the table is the median age of housing. While this can be a very effective measure, it can be misleading in cases where neighborhoods are transitioning. Following up on last week’s article on income changes, the median age of housing variable clearly shows many of the same shifts as many downtown and inner city neighborhoods are being redeveloped. The Cleveland, OH map clearly shows this phenomenon, as the downtown core has a significantly younger housing stock than the original suburbs of the city.
In San Francisco, the redevelopment along the eastern shore of the bay is clearly noticeable, as the city was reunited with its waterfront after the removal of the “blight by the bay” (the Embarcadero Freeway, SR 480) after the 1989 Loma Prieta earthquake. The redevelopment of the Mission Bay area is also clearly visible on the map.
The map of St. Louis shows the classic pattern which also tracks the growth of the city over time, with older housing in the city center and newer housing in the suburbs. A small area of redevelopment near the downtown core can be seen as well.