Building permits & new housing
The Census Bureau's building permits survey in Python: new housing by county since 1990, per resident and by building size, this year's months, and the header rows, imputed counts and Connecticut regions in the files.
The Census Bureau counts the new homes that local governments authorise: for every county, how many buildings, how many housing units and what they are declared to cost, by size of building, every year since 1990 and every month of the current year. In 2025 the US permitted 1,431,616 units, two thirds of the 2,155,316 of 2005. Permits are the earliest official sign of where housing is being built.
The guides here read the files, map permits per resident and the apartment share by county, chart the series since 1990, follow this year month by month, and set permits against population growth. Three pages deal with the traps: a file layout that a plain read_csv gets wrong, the imputed counts beside the reported ones, and Connecticut, whose counties became planning regions part-way through.
🧭 Start with the concepts
The ideas the how-to guides below assume you already have.
⚙️ Then do the task
Step-by-step walkthroughs with code you can copy and adapt.
- How to Read Census Building Permits Survey Data in Python
- How to Map New Housing Permits per 1,000 Residents by County
- How to Chart US Housing Permits Since 1990 in Python
- How to Measure the Apartment Share of New Housing by County
- How to Compare This Year's Housing Permits Month by Month
- How to Compare Housing Permits With Population Growth by County
🔧 When it breaks
The errors this topic produces, with the cause explained rather than just the command.
Related topics
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