The Building Technology Heritage Library (BTHL) is a collection of digitally reproduced American and Canadian, pre-1964 architectural trade catalogs, house plan books and technical building guides that are available via Archive.org. Trade catalogs are an important primary source to document past design and construction practices. These materials can aid in the preservation and conservation of older structures as well as other research goals. This scanning project was undertaken by the Association for Preservation Technology International (APT) with grant funding from the Preservation Education Foundation, the Driehaus Foundation, and the National Center for Preservation Technology and Training.
The M.S. Historic Preservation program at the School of the Art Institute (SAIC) has long had a relationship with APT. The program's director, Anne Sullivan, is a former President of the organization and was actively involved in the creation of the Building Technology Heritage Library (BTHL). Several years of SAIC Historic Preservation students were involved in preparing the scanned digital files in preparation for uploading to Archive.org. Many thanks to Kelsey Shipton ('12), Fleming Garner ('13), Megan Lydon ('14), Natalia Kwiatkowska ('14) and Alissa Hahn ('14 cert.) who worked diligently to help get this project online. APT has local chapters throughout the world, including in the midwest: APT WGLC - Western Great Lakes Chapter.