The Historic American Buildings Survey (HABS) and the Historic American Engineering Record (HAER) are two long-standing programs established to document the United States’ built heritage. These programs create a permanent public archive of significant architectural, engineering, and industrial sites. The resulting materials are maintained by the Library of Congress and serve as a valuable reference for preservation professionals, historians, architects, and government agencies.
HABS / HAER defined
HABS was established in 1933 as a federal program to document historic architecture. HAER followed in 1969 to record engineering and industrial structures. Both are administered by the National Park Service in cooperation with the Library of Congress and the private sector. Together, these programs provide detailed records of structures deemed historically or architecturally significant.
HABS / HAER documentation includes three core elements:
- Measured drawings created from field surveys or existing records
- Large-format black-and-white photographs that document exterior and interior conditions
- Written historical and descriptive reports
All materials submitted under HABS / HAER are reviewed for quality and consistency with established guidelines. When approved, they are archived at the Library of Congress for public access.
When HABS HAER Documentation is Required
Federal or federally funded projects that affect historic properties may require HABS/HAER documentation. This often occurs under Section 106 of the National Historic Preservation Act, which requires agencies to consider the impact of their undertakings on historic resources. If adverse effects cannot be avoided, mitigation may include documentation under the HABS or HAER standards.
Other scenarios where HABS HAER documentation may be used include:
- Preservation planning or restoration work
- Academic research or architectural studies
- Voluntary documentation by property owners
- Legal compliance during redevelopment of historic sites
In all cases, the goal is to provide an accurate, detailed, and permanent record of a site’s architectural or engineering significance.
Standards and Submission Requirements
HABS / HAER documentation must follow detailed standards published by the National Park Service. These include specific requirements for drawing scales, photography formats, narrative structure, and fieldwork methods. The intent is to produce materials that meet archival standards and remain useful over time.
Measured drawings must be produced on archival-quality media, typically using ink on Mylar or digital formats printed at full scale. Photography must be done with large-format film cameras, and the negatives processed and printed in accordance with archival specifications. Descriptive reports must include historical context, architectural or engineering analysis, and references to source materials.
Before submission, documentation is typically reviewed by a qualified architectural historian or preservation professional. The complete package is then sent to the Heritage Documentation Programs office for final review and transmittal to the Library of Congress.
Who Prepares HABS / HAER Documentation?
Professionals preparing these materials must demonstrate expertise in historical research, architectural documentation, and archival practices. This often includes licensed architects, preservation specialists, historians, and photographers with experience in heritage documentation. The site’s complexity and the intended use of the documentation influence the team’s composition.
Field surveys for measured drawings may use hand measurements, total stations, or laser scanning, depending on the required level of detail. However, the final output must comply with HABS / HAER standards regardless of the tools used in the field.
Benefits of Proper Documentation
While HABS / HAER documentation is often associated with regulatory compliance, it also serves broader purposes. For architects and preservationists, it creates a valuable baseline for future research, restoration, or interpretation. It captures not only the structure’s form but also its cultural and historical context.
In academic and professional circles, these records contribute to an understanding of regional building traditions, engineering innovations, and social history. For property owners and developers, documentation may be used to satisfy requirements while preserving a detailed record of the structure.
Final Considerations
HABS / HAER documentation is not interchangeable with general record drawings or basic photography. It requires strict adherence to standards, professional judgment, and a commitment to accuracy. For architects and preservationists, understanding these requirements is essential when working on projects that involve historically significant buildings or infrastructure.
Each submission becomes part of a national archive intended to serve future generations. Because of this, the quality and reliability of the documentation must be held to the highest standards. Professionals involved in this work should stay current with National Park Service guidelines and collaborate with experienced teams to produce complete and review-ready materials.
By following the established framework, HABS/HAER documentation contributes to the broader mission of preservation by safeguarding knowledge, documenting craftsmanship, and supporting public understanding of the built environment.