{"nrhp_refnum":"85002849","name":"Sibley Triangle Building","other_names":[],"category":"building","location":{"address":"20--30 East Ave.","address_restricted":false,"city":"Rochester","county":"Monroe County","state":"NY","lat":43.157453694000026,"lon":-77.60377229799997,"geom_source":"nps_gis"},"listed_date":"1985-10-04","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Architecture"],"significance_levels":["local"],"summary":{"what_it_is":"A five-story, flat-iron-shaped brick commercial building at 20-30 East Avenue in Rochester, Monroe County, New York, built in 1897 to a design by J. Foster Warner and constructed by T.W. Finucane.","why_significant":"The nomination presents it as a distinguished example of eclectic Italian Renaissance commercial design by Rochester's leading architect of the period, J. Foster Warner. Its triangular plan responds well to the site at Main Street and East Avenue and anchors two downtown streetscapes. It was also built for Hiram W. Sibley, a prominent realtor, banker and philanthropist.","narrative":"Occupying a triangular block where Main Street meets East Avenue in downtown Rochester, this five-story brick building was completed in 1897 for Hiram W. Sibley, a realtor, banker and philanthropist whose family wealth came from Western Union and the seed industry. J. Foster Warner, described as Rochester's leading architect of the era, designed it, and T.W. Finucane built it. The flat-iron plan makes efficient use of the awkward site. The first two stories are faced in Indiana limestone and marble, with pilasters topped by capitals carrying cartouches and garlands. Bowed Chicago-style windows mark the second floor, while the fifth story carries an arcade with roundels and a projecting terra-cotta cornice. The design echoes Warner's Monroe County Court House of 1894-1896. The building is valued as an Italian Renaissance commercial work that also contributes to two downtown streetscapes. Some storefront openings and East Avenue entrances were filled in around 1950, but the building remains in commercial use and in excellent condition.","period_of_significance":null,"architect_builder":"Architect J. Foster Warner; builder T.W. Finucane","architectural_style":"Eclectic Italian Renaissance commercial design","criteria":[],"status_note":"Listed in excellent condition and still in its original commercial use; the original storefront openings and East Avenue entrances were infilled around 1950.","vacant_flag":false,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:50:44.992452-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_NY/85002849.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/85002849/99a3dc5aa6-800.webp","url_1600":"https://nationalhistoricalregister.com/media/85002849/99a3dc5aa6-1600.webp","licence":"CC BY-SA 3.0","author":"Tim Pierce","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Sibley_Triangle_Building.jpg\" rel=\"noopener\">Tim Pierce</a>, <a href=\"https://creativecommons.org/licenses/by-sa/3.0\" rel=\"license noopener\">CC BY-SA 3.0</a>, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:Sibley_Triangle_Building.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/75313583","wikipedia":"https://en.wikipedia.org/wiki/Sibley_Triangle_Building","wikidata":"https://www.wikidata.org/wiki/Q7507213"},"indexable":true,"url":"https://nationalhistoricalregister.com/new-york/monroe-county/sibley-triangle-building-85002849/"}