{"nrhp_refnum":"10000404","name":"Steel Heddle Manufacturing Company Complex","other_names":[],"category":"building","location":{"address":"2100 W Allegheny Ave","address_restricted":false,"city":"Philadelphia","county":"Philadelphia","state":"PA","lat":40.005118105000065,"lon":-75.16593787699998,"geom_source":"nps_gis"},"listed_date":"2010-06-28","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Industry"],"significance_levels":["local"],"summary":{"what_it_is":"A complex of four interconnected industrial buildings (Plant, Main Office, Chrome Plating Building, Lumber Storage and Garage Building) on a site at the southwest corner of West Allegheny Avenue and North 21st Street in the Allegheny West neighborhood of Philadelphia, built in stages between 1919 and 1951. It was the main plant and headquarters of the Steel Heddle Manufacturing Company, a maker of textile loom accessories.","why_significant":"The nomination argues the complex is significant under Criterion A in the area of Industry because the Steel Heddle Manufacturing Company was a leading manufacturer and distributor of weaving loom accessories and developed the first single-piece flat steel heddle, which made looms more efficient and durable than wire heddles. It also places the company within Philadelphia's large textile industry. The level of significance is stated as local.","narrative":"Built in stages from 1919 to 1951 on a corner site in Philadelphia's Allegheny West neighborhood, the complex is centered on a five-story reinforced concrete and brick plant laid out in a U-shape with mushroom columns and industrial steel sash windows. Steel Heddle Manufacturing Company, which had been founded in 1898 in Germantown, used the site as its main factory and headquarters for decades. The company patented the first flat steel heddle in the United States, a stamped part that outlasted the twisted wire heddles it replaced and let mills weave heavier fabrics with greater loom efficiency. Its steel heddles were widely adopted by American silk mills. The complex also includes a four-story brick Main Office, originally built for a window shade maker, a one-story chrome plating building from 1951 and a lumber storage and garage. Manufacturing continued on the site until 1971, and Philadelphia operations ceased in 1983.","period_of_significance":"1919-1959","architect_builder":"William Steele and Sons Company","architectural_style":"Late 19th and early 20th century American Movements/Commercial Style","criteria":["A"],"status_note":"Vacated in 2006 after use for paper recycling and telecommunications following the company's 1983 closure of Philadelphia operations.","vacant_flag":true,"machine_generated":true,"model":"claude-haiku-5-5","prompt_version":"v1.1-2026-10-29","generated_at":"2026-10-29 17:10:27.197911-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_PA/10000404.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/10000404/99722d794b-800.webp","url_1600":"https://nationalhistoricalregister.com/media/10000404/99722d794b-1600.webp","licence":"Public domain","author":"Smallbones","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Steel_Heddle_Philly.JPG\" rel=\"noopener\">Smallbones</a>, Public domain, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:Steel_Heddle_Philly.JPG"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/71997496","wikipedia":"https://en.wikipedia.org/wiki/Steel_Heddle_Manufacturing_Company_Complex","wikidata":"https://www.wikidata.org/wiki/Q7605682"},"indexable":true,"url":"https://nationalhistoricalregister.com/pennsylvania/philadelphia/steel-heddle-manufacturing-company-complex-10000404/"}