For the researcher investigating the built environment of New York City, material contained within the Municipal Archives is a gold mine. Recent blogs have described three of these resources, the Assessed Valuation Real Estate Ledgers, the Manhattan Department of Buildings docket books, and the Manhattan building plan collection, part 1, and part 2.

This week’s subject is another series from the Department of Buildings Record Group (025)—the application permit folders, a.k.a. the block and lot folders. The series is a subset of the Department of Buildings Manhattan Building Plan Collection, 1866-1977 (REC 074).

Totaling approximately 1,230 cubic feet, the permit folders provide essential and detailed construction and alteration information for almost every building in lower Manhattan from the Battery to 34th Street. In addition, a wide range of historical subjects can be explored using these records including the effect of planning, zoning and technology on building design, the role of real estate development as a gauge of national economic trends, and the evolution of architectural practice, particularly during the period of professionalization in the latter part of the 19th century.

Established in 1862, the Department of Buildings (DOB) “had full power, in passing upon any question relative to the mode, manner of construction or materials to be used in the erection, alteration or repair of any building in the City of New York.” All DOB personnel were required to be architects, masons, or house carpenters. Then, beginning in 1866, New York City law required that an application, including plans, be submitted to the DOB for approval before a building could be constructed or altered.

The provenance of the collection in the Municipal Archives dates to the 1970s when the DOB began microfilming the application files and plans as a space-saving measure. They intended to dispose of the original materials after microfilming. The project began with records of buildings in lower Manhattan, proceeding northward to approximately 34th Street when it was discovered that the microfilm copies were illegible. The DOB abandoned the project and the original records were transferred to the Municipal Archives for permanent preservation and access. 

New Building (NB) Applications

In theory, there should be an NB application for every building constructed after 1866. Unfortunately, prior to the mid-1960s, DOB policy was to dispose of the files of buildings that were demolished. The result is that the Municipal Archives collection generally comprises only records of buildings extant as of the mid-to-late 1970s.

The NB application provides the most complete and detailed information about a structure. The form includes location (street address and block and lot numbers); the owner, architect and/or contractors; dimensions and description of the site; dimensions of the proposed building; estimated cost; the type of building (loft, dwelling factory, tenement, office, etc.); and details of its construction such as materials to be used for the foundation, upper walls, roof and interior. Every NB application was assigned a number, beginning with number one for the first application filed on or after January 1, up to as many as 3,000 or more by December 31, each year.

As buildings incorporated new technologies such as elevators and steel-frame construction, the approval process became more rigorous, requiring more extensive information about the proposed structure. Permit folders for larger buildings often contain voluminous back-and-forth correspondence between the DOB examiners and the owners and architects. If any part of an NB application was disapproved the owner or architect was obliged to file an “Amendment” form stating what changes would be made to the application so that the building would comply with building codes.   

When the DOB approved a NB application, they issued a permit and construction could begin. Periodically during construction, inspections would be made by DOB personnel and their reports would also be included in the application file.

Other Applications

After a building was completed and the final inspection report submitted, any subsequent work on the building would require a separate Alteration (ALT) application. As building technology became more complex, the DOB began to require separate applications for elevator and dumbwaiter installations, plumbing and drainage work, certificates of occupancy and electric signs. The permit files also contain numerous Building Notice (BN) applications pertaining to relatively minor alterations. The DOB also mandated a “Demolition” application to raze buildings. The permit files generally do not include documents related to building violations.

The DOB organized all applications and related correspondence into folders according to the block and lot where the building was situated. After 1898, each block in Manhattan was assigned a number, beginning with number 1 at the Battery, and each lot within the block was also assigned a number. The original block and lot filing scheme has been maintained by the Municipal Archives for the block and lot permit collection. An inventory of the permit folder collection is available in the new online Municipal Archives Collection Guides.  

The Municipal Archives has also maintained the original permit folders, whenever possible. The folder lists the application paperwork contained within and serves as a table of contents. If paperwork related to an application listed on the folder is missing, it is possible to trace at least basic information about the action using the DOB docket books as described in a recent blog Manhattan Department of Buildings docket books.

The collection provides detailed data about specific buildings and enables the researcher to explore broader topics. For example, one theme of interest to architectural historians is the impact of New York’s 1916 zoning ordinance. The regulation had been imposed partly in response to construction of the massive Equitable Building on lower Broadway, but more generally to reduce the growing density of the built environment. It is usually argued that the law was responsible for the setback style of New York skyscrapers constructed throughout the 1920s. In an examination of the NB applications for several skyscraper buildings erected before the Depression, such as the Irving Trust tower at 1 Wall Street, it was found that very often the original NB application was disapproved, in part because the building plans violated some part of the 1916 zoning ordinance. In response, however, the architects did not revise their plans, but instead appealed to the City for a variance and invariably received permission to proceed with their original plans.

The permit folder collection also provides ample opportunity for researchers to study the long tradition of adaptive re-use of buildings in lower Manhattan. Although many of the buildings in these neighborhoods pre-date establishment of the DOB, the collection is rich with applications submitted for later alterations, as architects, homeowners, and developers converted older structures into “modern” dwellings by removing stoops and covering facades with light-colored stucco, mosaic tile, and shutters. 

The permit folders, along with the associated building plans, contain documentation for the study of individual architects, as well as architecture as a profession. Scholars will find an abundance of unique materials that detail the professionalization of the field, especially during the latter half of the 19th century.

Together with the Assessed Valuation of Real Estate ledgers, the several Department of Buildings series—docket books, architectural plans, and the permit folders, provide an unparalleled opportunity for detailed research on the built environment. Few other cities in the nation possess a body of documents whose scope and completeness can compare with these New York City records.