The flexible urban grid: adaptation, expansion and evolution in Philadelphia's city block morphology
his study examines the evolution of Philadelphia’s city block morphology between 1683, when the city was planned by William Penn, and 1900, when urban expansion abandoned the grid. The study uses both quantitative and qualitative assessment. The city grid underwent evolution during this...
| Main Authors: | , |
|---|---|
| Other Authors: | |
| Format: | Article |
| Language: | en_US |
| Published: |
International Seminar on Urban Form
2024
|
| Online Access: | https://hdl.handle.net/1721.1/157552 |
| _version_ | 1824458129746690048 |
|---|---|
| author | Ryan, Brent D. Wang, Elaine |
| author2 | Massachusetts Institute of Technology. Department of Urban Studies and Planning |
| author_facet | Massachusetts Institute of Technology. Department of Urban Studies and Planning Ryan, Brent D. Wang, Elaine |
| author_sort | Ryan, Brent D. |
| collection | MIT |
| description | his study examines the evolution of Philadelphia’s city block morphology between 1683, when the city was planned by William Penn, and 1900, when urban expansion abandoned the grid. The study uses both quantitative and qualitative assessment. The city grid underwent evolution during this time that resolved deficiencies of the original Penn plan, improving circulation and maximizing block area for rowhouse development. The Penn grid had large rectilinear blocks with irregular dimensions: it experienced two types of evolution. The first was adaptation through infill, as large 1683 blocks were subdivided by secondary through streets and tertiary streets. The second was adaptation through expansion of the grid, first an irregular, ‘unplanned’ grid, and later a regular, ‘planned’ grid. Both expansions reduced 1683 block depths to permit additional east- west circulation and to increase developable block frontage. Mean block depths of 666 ft in the Penn grid were reduced to 383 ft in the adapted grid, to 328 ft (south) and 393 ft (north) in the unplanned expansion grid, and to 422 ft (south) and 534 ft (north) in the planned expansion grid. In the expansion grid, tertiary streets and rowhouse dimensions and heights were integrated with quaternary streets (pedestrian alleys), permitting high levels of housing density and diversity. |
| first_indexed | 2025-02-19T04:20:59Z |
| format | Article |
| id | mit-1721.1/157552 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2025-02-19T04:20:59Z |
| publishDate | 2024 |
| publisher | International Seminar on Urban Form |
| record_format | dspace |
| spelling | mit-1721.1/1575522025-01-04T05:46:00Z The flexible urban grid: adaptation, expansion and evolution in Philadelphia's city block morphology Ryan, Brent D. Wang, Elaine Massachusetts Institute of Technology. Department of Urban Studies and Planning his study examines the evolution of Philadelphia’s city block morphology between 1683, when the city was planned by William Penn, and 1900, when urban expansion abandoned the grid. The study uses both quantitative and qualitative assessment. The city grid underwent evolution during this time that resolved deficiencies of the original Penn plan, improving circulation and maximizing block area for rowhouse development. The Penn grid had large rectilinear blocks with irregular dimensions: it experienced two types of evolution. The first was adaptation through infill, as large 1683 blocks were subdivided by secondary through streets and tertiary streets. The second was adaptation through expansion of the grid, first an irregular, ‘unplanned’ grid, and later a regular, ‘planned’ grid. Both expansions reduced 1683 block depths to permit additional east- west circulation and to increase developable block frontage. Mean block depths of 666 ft in the Penn grid were reduced to 383 ft in the adapted grid, to 328 ft (south) and 393 ft (north) in the unplanned expansion grid, and to 422 ft (south) and 534 ft (north) in the planned expansion grid. In the expansion grid, tertiary streets and rowhouse dimensions and heights were integrated with quaternary streets (pedestrian alleys), permitting high levels of housing density and diversity. 2024-11-15T21:32:07Z 2024-11-15T21:32:07Z 2023 Article http://purl.org/eprint/type/JournalArticle https://hdl.handle.net/1721.1/157552 Ryan, B., & Wang, E. (2023). The flexible urban grid: adaptation, expansion and evolution in Philadelphia’s city block morphology. Urban Morphology, 27(1), 3–30. en_US https://doi.org/10.51347/UM27.0001 Urban Morphology Creative Commons Attribution-Noncommercial-ShareAlike http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf International Seminar on Urban Form |
| spellingShingle | Ryan, Brent D. Wang, Elaine The flexible urban grid: adaptation, expansion and evolution in Philadelphia's city block morphology |
| title | The flexible urban grid: adaptation, expansion and evolution in Philadelphia's city block morphology |
| title_full | The flexible urban grid: adaptation, expansion and evolution in Philadelphia's city block morphology |
| title_fullStr | The flexible urban grid: adaptation, expansion and evolution in Philadelphia's city block morphology |
| title_full_unstemmed | The flexible urban grid: adaptation, expansion and evolution in Philadelphia's city block morphology |
| title_short | The flexible urban grid: adaptation, expansion and evolution in Philadelphia's city block morphology |
| title_sort | flexible urban grid adaptation expansion and evolution in philadelphia s city block morphology |
| url | https://hdl.handle.net/1721.1/157552 |
| work_keys_str_mv | AT ryanbrentd theflexibleurbangridadaptationexpansionandevolutioninphiladelphiascityblockmorphology AT wangelaine theflexibleurbangridadaptationexpansionandevolutioninphiladelphiascityblockmorphology AT ryanbrentd flexibleurbangridadaptationexpansionandevolutioninphiladelphiascityblockmorphology AT wangelaine flexibleurbangridadaptationexpansionandevolutioninphiladelphiascityblockmorphology |