Structure types · Building Permits Survey
3-to-4 unit structures
Small multifamily buildings with three or four housing units.
This category covers structures with three or four housing units — triplexes and fourplexes. Along with 2-unit structures, it makes up the small-scale 'missing middle' between detached houses and large apartment buildings.
Also known as: triplex, fourplex.
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3-to-4 unit structures — FAQ
What is 3-to-4 unit structures in building permits data?+
Small multifamily buildings with three or four housing units. This category covers structures with three or four housing units — triplexes and fourplexes. Along with 2-unit structures, it makes up the small-scale 'missing middle' between detached houses and large apartment buildings.
Where does this building-permit data come from?+
All figures come from the U.S. Census Bureau's Building Permits Survey (BPS), a monthly census of permit-issuing jurisdictions. PUMSdata is an independent product that makes it easy to map and compare, and is not affiliated with the Census Bureau.