The first chart compares Arapahoe County with the Colorado average and the other large counties in the state for the median year of residential housing construction. The Arapahoe County value of 1987 means that half the housing was older than 1987 and half was newer. The housing in Arapahoe County was slightly older than the Colorado median, 1989. Pueblo and Denver Counties had by far the oldest housing with a median year built of 1974 and 1970, respectively. Weld County had a median year built of 2009, while Broomfield and Douglas counties each had a median year of 2004.

The next chart shows the number of units added since 2019 for each county. Arapahoe County ranked sixth with 11,358 new units, behind Douglas County. While Denver County had the second-oldest median year built, it also had the most units added since 2019 at 29,537.

Digging into Arapahoe County details, the next chart shows the distribution of housing units by age and for owners and renters. The 1980s were ahead of the 1970s for the peak decade for housing units with 59,400 total units. The number of units in the 2010s dropped to nearly half those built in the 2000s. The 2020 decade so far has been running behind the 2010s. This might be the slowest decade since the 1960s unless building rates pick up.