How to Read a Kirksville Sanborn Fire Insurance Map

Sanborn fire-insurance maps can look like a pile of colored boxes and cryptic letters until you understand what they were made to document.

They were insurance maps.

Their job was to describe fire risk.

That purpose is exactly why they are so useful for researching old Kirksville buildings.

Start with the Kirksville set

The Library of Congress has a digitized August 1914 Sanborn Fire Insurance Map from Kirksville, Adair County, Missouri.

The set contains 14 sheets.

Do not open random sheets until you have checked the index or key map.

Why Sanborn maps contain so much detail

Sanborn maps were designed to help insurers evaluate hazards.

They can show:

• building footprint;
• construction material;
• number of stories;
• building use;
• doors and openings;
• fire walls;
• street widths;
• property relationships;
• water mains;
• hydrants;
• fire alarms.

That makes one map useful for architecture, infrastructure, business and neighborhood research at the same time.

Read the map's own legend

Common Sanborn colors often include:

• yellow for frame construction;
• pink or reddish tones for brick;
• blue for some concrete or block construction.

But do not memorize one internet legend and apply it blindly.

Sanborn conventions changed.

Use the actual key for the edition you are reading.

Read the footprint

The outline of the building can reveal:

• porches;
• additions;
• attached structures;
• outbuildings;
• setbacks;
• relationship to neighboring buildings.

Comparing editions can show when a structure expanded or disappeared.

It usually cannot prove the exact day or year construction occurred.

It brackets the change between surveys.

Read building use carefully

Abbreviations may identify uses such as:

• dwelling;
• store;
• flat;
• saloon.

A generic label such as "store" does not tell you the business name.

Use a city directory or newspaper to identify the actual occupant.

Use the address, but do not worship it

Sanborn maps often show street and house numbers.

That can be extremely useful when Kirksville addresses changed.

Still, the map belongs to its own date.

A 1914 number should not be assumed to equal a modern number.

Look beyond individual buildings

Introductory or key material can also describe:

• fire department;
• hydrants;
• water mains;
• alarms;
• water pressure;
• other municipal infrastructure.

That makes Sanborn maps useful for understanding how the city functioned, not merely what one house looked like.

Know the limits

Sanborn maps were not legal cadastral surveys.

Do not use their lines as definitive property boundaries.

Coverage can also stop before rural or outlying areas, so absence from the map does not necessarily mean the land was vacant.

Combine the map with other records

The strongest interpretation uses several sources:

• Sanborn map;
• city directory;
• historic photograph;
• deed;
• newspaper.

For broader map-to-modern comparisons, see How to Compare Historic Kirksville Maps With Today’s Streets.

Once you learn to read the key, those colored boxes stop looking mysterious and start looking suspiciously like a century-old municipal database drawn by hand.