Actually, the digital scans of the Sanborn maps available at the Library of Congress are from a company called ProQuest. They offer a subscription service, although you can sign up for a free trial. This is a link to a description of their Sanborn maps product:
http://www.proquest.com/assets/literature/products/databases/gsm.pdf The Library of Congress does have a full index of the Sanborn maps available online at the URL Ward Bucher cited, but only those few jurisdictions marked with an asterisk (DC is one of them) have maps that can be downloaded. If you go to the Library of Congress in person, you can download all of the Sanborn digital maps from any LC research computer (you are not limited to the ones in the Geography and Maps Reading Room). You can e-mail them to yourself, but I have found that it is more reliable to download them directly to a USB flash drive.
An alternative is to find a nearby library that has a subscription to ProQuest and access them there. Likely candidates are state, major city, and university libraries.
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John Burns FAIA
Chief Appeals Officer
National Park Service
Alexandria VA
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Original Message:
Sent: 05-07-2013 05:56
From: Ward Bucher
Subject: Dating Buildings (NOT a singles website)
To access the Sanborn Maps try www.loc.gov/rr/geogmap/sanborn/. This is a US Library of Congress website that has many US, Canada, Mexico maps and limited Cuba maps. One can search these images without a password.
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Ward Bucher AIA
Bucher/Borges Group PLLC
Easton MD
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Original Message:
Sent: 05-04-2013 07:04
From: Stephanie Bock
Subject: Dating Buildings (NOT a singles website)
How do you acquire a log in/password to the Sanborn site?
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Stephanie Bock AIA
Savannah GA
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