The Sanborn Map Publishing Company produced amazing fire Insurance maps across North America from 1867 to 1969. Surveyor D.A. Sanborn designed these specialized maps to assist fire insurance agents in determining the degree of hazard with particular properties.
They were terribly expensive to buy at the time – with a price of $ 50. in 1885 – so companies must have thought hard before agreeing to purchase them. However, these maps were the cutting edge information of their day, and they made it possible for fire insurance agents to assess potential danger to a structure without leaving their offices, simple by consulting the appropriate map.
Carefully surveyed, and meticulously hand-drawn and coloured, the maps showed outlines of all the buildings, both commercial and residential, in an accurate manner, with appended notes as to the height of the building, observations on odd construction, and the use of specialized structures, such as theatres, churches and hospitals. Notes such as “steep hill” or “Cooperage” (a barrel making building) added to the insurance agent’s information.
By using colour, the maps indicated which material was used to construct the building. Pink for brick buildings, yellow for wood structures and blue for stone. Iron buildings were grey, and, for regional variation, adobe buildings were coloured olive.
For owners of old houses, and other interested researchers, these maps are invaluable, as they sometimes are the only record of what the buildings looked like in their early years – at least before Google maps happened on the scene!
Found today at archives and map libraries, and sometimes at old time insurance offices still, where they might be kept as curiosities, these treasuries of information can answer all sorts of questions about your house and surrounding structures.
The maps were regularly updated by pasting new drawings over redeveloped properties. Sometimes, shining a flashlight up through the paper can reveal the underlying drawings and the former configuration of the building in question.
We all owe a great debt to the historic Sanborn Company for recording the buildings of North America so meticulously. Sometimes the only record of changes or alterations to our Old Houses and their neighborhoods are found in these masterpieces of observation.
The terms “Sanborn” and “Sanborn Maps” are registered trademarks owned by The
Sanborn Library, LLC.