> For the complete documentation index, see [llms.txt](https://docs.os.uk/osngd/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/osngd/code-lists/code-lists-overview/buildingageperiodvalue.md).

# buildingageperiodvalue

This code list is used in association with the Building Age Period attribute which is present within the Building Feature Type. The code list describes the building construction periods represented in the data.

| Label     | Definition                                                                                                                                                                                                 |
| --------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Pre-1837  | Building constructed before 1837. Historic to end Georgian. This more detailed period is provided if suitable information is available, otherwise the more general Pre-1919 period is applied.             |
| Pre-1919  | The broad Pre-1919 period is applied if insufficient information was available to provide one of the more detailed periods: Pre-1837, 1837-1869 or 1870-1918.                                              |
| 1837-1869 | Building constructed between 1837 and 1869. Early and Middle Victorian. This more detailed period is provided if suitable information is available, otherwise the more general Pre-1919 period is applied. |
| 1870-1918 | Building constructed between 1870 and 1918. Late Victorian/Edwardian. This more detailed period is provided if suitable information is available, otherwise the more general Pre-1919 period is applied.   |
| 1919-1944 | Building constructed between 1919 and 1944.                                                                                                                                                                |
| 1945-1959 | Building constructed between 1945 and 1959.                                                                                                                                                                |
| 1960-1979 | Building constructed between 1960 and 1979.                                                                                                                                                                |
| 1980-1989 | Building constructed between 1980 and 1989.                                                                                                                                                                |
| 1990-1999 | Building constructed between 1990 and 1999.                                                                                                                                                                |
| 2000-2009 | Building constructed between 2000 and 2009.                                                                                                                                                                |
| 2010-2019 | Building constructed between 2010 and 2019.                                                                                                                                                                |
| 2020-2029 | Building constructed between 2020 and 2029.                                                                                                                                                                |
| 2030-2039 | Building constructed between 2030 and 2039.                                                                                                                                                                |
| Unknown   | The period of construction could not be determined, or has not yet been determined. Note that Unknown is only applied to buildings that are in scope of construction period capture.                       |


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