Residential projects that are neither single-family homes nor large apartment developments are often referred to as the missing middle of the construction sector. This includes medium-density housing like townhouses, duplexes and other small multifamily properties.
While townhouse construction has trended higher in recent quarters, the multifamily segment of the missing middle (apartments in 2 to 4 unit properties) has disappointed. For 2021, there were only 12,000 starts of such residences. This is flat from from 2020, during a period of time when most market segments expanded.
NAHB Chief Economist Rob Dietz provides more analysis in this Eye on Housing blog post.
Learn more about missing middle housing.