{"nrhp_refnum":"07000031","name":"Rohm and Haas Corporate Headquarters","other_names":[],"category":"building","location":{"address":"100 Independence Mall West","address_restricted":false,"city":"Philadelphia","county":"Philadelphia","state":"PA","lat":39.95036728800005,"lon":-75.15094934799998,"geom_source":"nps_gis"},"listed_date":"2007-02-09","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Architecture"],"significance_levels":["national"],"summary":{"what_it_is":"A nine-story reinforced concrete office headquarters on the western edge of Independence Mall in Center City Philadelphia, built 1963-65 for the Rohm and Haas Company. It was designed by Pietro Belluschi with the George M. Ewing Company as executive architect.","why_significant":"The nomination argues the building is an important example of Modern Movement architecture in Philadelphia, with exposed reinforced concrete, bronze-anodized aluminum and Plexiglas elements, and a horizontal form that relates to Independence Mall. It also cites the building's innovative use of the company's Plexiglas and its status as one of only two Belluschi works in the city.","narrative":"Located on the western boundary of Independence Mall in Center City Philadelphia, this nine-story office headquarters was designed by Pietro Belluschi and built between 1963 and 1965 for the Rohm and Haas Company. A reinforced concrete structure rises above a full basement, with its columns and projecting balcony-like floor slabs fully expressed on the exterior. The first story is a colonnade of prismoidal concrete columns, and the upper floors are clad in bronze-colored anodized aluminum windows, bronze Plexiglas spandrels and corrugated Plexiglas sunshades. A 60-foot-wide galleria divides the ground floor into two pavilions, and granite-walled plazas surround the building. The building is regarded as a leading Philadelphia example of Modern Movement design, with exposed concrete and experimental use of the company's Plexiglas. It also reflects the city's urban renewal effort to keep corporations in the downtown core and the company's move from Washington Square.","period_of_significance":"1963-65","architect_builder":"Belluschi, Pietro (architect); George M. Ewing Company (builder)","architectural_style":"Modern Movement","criteria":["C"],"status_note":"The south pavilion is described as currently vacant.","vacant_flag":true,"machine_generated":true,"model":"claude-haiku-5-5","prompt_version":"v1.1-2026-10-29","generated_at":"2026-10-29 17:10:27.146564-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_PA/07000031.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/07000031/e234234adb-800.webp","url_1600":"https://nationalhistoricalregister.com/media/07000031/e234234adb-1600.webp","licence":"CC BY-SA 4.0","author":"Beyond My Ken","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Rohm_and_Haas_Building.jpg\" rel=\"noopener\">Beyond My Ken</a>, <a href=\"https://creativecommons.org/licenses/by-sa/4.0\" rel=\"license noopener\">CC BY-SA 4.0</a>, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:Rohm_and_Haas_Building.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/71996992","wikipedia":"https://en.wikipedia.org/wiki/Rohm_and_Haas_Corporate_Headquarters","wikidata":"https://www.wikidata.org/wiki/Q7359784"},"indexable":true,"url":"https://nationalhistoricalregister.com/pennsylvania/philadelphia/rohm-and-haas-corporate-headquarters-07000031/"}