Introduction
When you think of insurance, maps might not be the first thing that comes to mind, but fire insurance maps have been around since the late 1800s and are still being used today.
Sanborn Fire Insurance Maps are pre-drawn and pre-colored maps that show information about the buildings in an area and their general condition. The data collected includes building height, number of stories, type of construction, materials used, occupancy, and much more.
These data help firefighters know how to approach burning buildings quickly and safely to minimize damage to surrounding properties and people.
History of Sanborn Fire Insurance
Sanborn fire insurance maps date back to 1867 and started as a response to the Great Chicago Fire. The maps were created by Louis Sanborn, who at the time was working for a local firm that specialized in fireproof building design. What makes these maps so interesting is that they offer an invaluable record of some of America's greatest urban centers as they developed over the span of more than 150 years.
These records are not only useful for studying urban development but also for understanding how much fire risk there is in certain areas. At the same time, they provide a rich visual overview of a city's changing built environment.
With the data gathered from the various maps you can study building materials used in each era and their effects on fires; population densities; where industrial zones tended to be located; where vacant lots appeared (and disappeared); and why certain neighborhoods have been destroyed or redeveloped.
The initial survey was conducted primarily in Boston, Massachusetts, and its immediate vicinity. Within two decades, coverage had expanded nationwide with a greater emphasis on major cities such as New York City and Philadelphia.
How Are They Made?
After a map was made, a lithographer would use this as a guide to creating an engraving or printing plate. Each individual building on the map was drawn by hand and then inked onto the lithograph stone. These stones were then flooded with water and the area around each building was washed clean. The pattern of ink left on the stone created the corresponding printing plates.
This process of carving out spaces is similar to using stamps in arts and crafts that allow an image to be printed out over and over again, only instead of producing just one copy it produces thousands! For instance, if you look at the 1871 fire insurance map of New York City below you can see that there are small markings above some buildings (indicating their height) and larger markings next to other buildings (indicating their height).
If you compare these two maps together you will see how much has changed about the city in just 100 years! For example, where there was once a train station on the west side of town now stands a huge office building.
It's interesting to think that because they had access to all of this information back then people could better plan for things like fires than we can today.
Why are they important?
Although people may not be aware of the term, everyone has seen a Sanborn fire insurance map at some point. These maps are essentially early versions of Google Earth because they show both ground and aerial views of cities from the early 20th century.
Even though they might seem outdated by our standards, they can provide very valuable information on everything from urban development to what types of buildings were in use in an area during that time period.
To see these beautiful maps for yourself and learn more about how they were made, check out the National Archives website here!
The name Sanborn is derived from two brothers who were involved in founding it: Henry Sanborn and Aaron Lyle Sanborn. The company was founded back in 1866 when it began selling insurance policies with maps attached showing all known buildings within city limits.
The maps became popular due to their usefulness to fire insurance agents, who could then determine the risk level associated with insuring certain buildings if a fire broke out.
Where do I find them now?
Sanborn maps are fire insurance maps that were made by Sanborn Map Company from 1867-1970. They cover all of the United States and are valuable for urban planning and analyzing patterns of urban development, suburban expansion, rural growth, and other shifts in land use.
A digital library has been created of over 1,000,000 scans from 1890-the 1930s. In addition to public libraries throughout the U.S., digital copies are also available at a number of universities throughout North America including Michigan State University and Tulane University.
Both open and subscription options are available to view these historic records on your computer or mobile device.
Open access materials may be freely downloaded and printed out as desired, but you must register with us before printing anything out (printing is unlimited).
Subscription access allows up to 100 prints per month with full rights.
0 Comments