FAQs / Help for Sanborn Fire Insurance Maps
How many Sanborn sheets does the Library of Congress have?
The Library of Congress, Geography and Map Division
holds approximately 675,000 Sanborn sheets in its collections. This collection is
one of the largest in the world and continues to grow.
Is it possible to search the Library's online catalog for Sanborns?
Only a few Sanborn sheets are actually
cataloged. The expansiveness of the collection makes it more efficient to use a separate,
searchable database to
reflect holdings in the Geography and Map Division of the Library of Congress. Sanborn
maps acquired since 1981 (the date of the original printed guide Fire Insurance Maps
in the Library of Congress) are added to the database.
Are all the Sanborn sheets available to be viewed online?
Out of copyright maps (printed before
January 1st, 1923) will be made available on this site, only after
the complete year or volume has been scanned. New images will
be made available as soon as possible. We will link the scanned image to the
entry within the "URL" field of the database.
How may I obtain a copy of a Sanborn sheet?
It is possible to request a digital copy of a sheet
or set of sheets that are out of copyright through the Library
of Congress Photoduplication Service. A listing of prices is located
Digital Imaging Services
page and is also available by calling 202-707-5640.
If a sheet has already been scanned it is
considered to be an existing file and can be purchased for a different
fee than requesting a scan from original material.
Downloading JPEG2000 (JP2) files is possible
by clicking on the Download JPEG200 image link below the
Zoom View. The number in this link indicates the size of the compressed
image. The Library maintains a list of links to software for viewing
downloaded JPEG2000 files on its "How
to View" page. As of July 2006, OS X supports viewing baseline JPEG2000
files natively; additional software may be needed to view large format
JPEG2000 files on a
MacIntosh computer. The Library of Congress cartographic JPEG2000
files are compressed at a ratio of 20:1.
How do I "Zoom" into a map?
At the bottom of each "Zoom View" and "Navigator
window are radio buttons, used to determine the size of the "Zoom
View" and the magnification.
- First, choose a "Zoom View" size
- Second, choose a magnification level
- Finally, "click" on an area of the map
How is a Sanborn map interpreted or read?
ook for the map key
often at the beginning of books, but not always. This will assist
in the interpretation of the map.
Fire insurance maps indicate many different building structures
and codes through colors and symbols. Different building materials
and resources resulted in different
building styles and representations on the maps. For example, the
use of adobe will not be seen in states East of the Mississippi
River. Read more about this in the following essays:
How to Interpret Sanborn Fire Insurance Maps
Sanborn Time Series
Why are copyrighted items listed if they are not available for reproduction?
The Geography and Map Sanborn Fire Insurance
Maps collections spans from 1844 - 1995. The U.S. Copyright law prohibits
the Geography and Map Division from reproducing items still in copyright. To assist
researchers, the Geography and Map Division provides as complete a listing as is
possible. Searching the database allows researchers to determine specific coverage
prior to coming to the Library of Congress or contacting the nearest institution.
The section, Related Resources, provides a listing of the organization (library,
archive, or historical association) with Sanborn Fire Insurance collections.
The Geography and Map Division has a long-term goal of
scanning all its out-of-copyright sheets from the Sanborn Fire Insurance Map Collection.
If you (or your institution) have any questions regarding the scanning of the Sanborn maps, please contact:
Geography & Map Division
Library of Congress