Fire Insurance Maps: General Information About

These maps, as the name indicates, were created for use in the insurance industry so underwriters would have accurate information about the structures for which they were asked to write fire insurance. Often the company employees would write in pencil, on or near the structure on the map, the number of the policy they had written.

The structures on the maps were colored coded: yellow stood for frame; red for brick; blue for stone; and brown for fireproof construction. In addition, there were other discrete types of information such as the height of the structure, location on the lot or lots, relation to other structures in the area, and location of sewers and water mains. The type of the structure was also noted. “D” stood for dwelling, which could be either a single family home or a two flat. “F” stood for a flat building of three or more units. For commercial structures, the map might also indicate additional information, such as the type of business, e.g. drug, bakery, laundry, bowling alley.

Surveyors would go out and take measurements of the structures, recording the specifics about them. At headquarters, map makers would take this information and create an outline to scale of the structure, and place it in the appropriate place on the individual map sheets. The final printed sheets (about 25 x 21 inches) would be bound in large books for specific areas and the books sold to individual insurance brokers (or anyone else who wanted them). In addition to selling the books, the companies often sold update services. The areas would be periodically re-surveyed and any changes noted, e.g., a rear addition or a demolition. Instead of replacing the books or even the individual sheets, the companies that produced the books would send out employees to the firms that subscribed to the service and they would update the firms’ books. They would do this by pasting small pieces of paper showing the changes over the structure that had changed.

Initially, there were several companies that produced fire insurance maps, including the Rascher Company, for whom Rascher Street was named. However, in time the Sanborn Map company became the dominant player. It did so by buying out a number of its competitors, including Rascher. The Sanborn company continued to produce and update maps into the 1950s.

Different communities and sections of large cities had maps produced at different times. In Chicago, not all sections had maps for the same years. Edgewater was fortunate. Maps were produced in 1887, 1894, 1905 and 1928. The Chicago History Museum has the bound volumes of all these maps. The maps produced in 1887 (Rascher) and 1894 (Sanborn) did not cover all of Edgewater, only the more developed parts. By 1928, Edgewater was mostly built up, though east of Broadway there would be significant changes that would follow, most of which, however, were not recorded by the fire insurance maps because they occurred after the company stopped producing updates. Thus, the 1905 map is the most useful as a snapshot of development at the time it was produced.

Note: We’ve made the 1905 Sanborn maps available to you on this website. It is easiest to select the desired sheet if your PDF viewer can display bookmarks (as does Adobe Reader). Here is a link to the Maps index in which “Fire-insurance maps” is a section.