Find many proposed and designated landmark reports for Chicago buildings and neighborhoods (many, but not all).
The Chicago History Museum holds many resources for researching the history of Chicago building, whether you want to know something about your condo in a former shoe factory, a bungalow on the west side, or a downtown commercial building. A visit to the Research Center will provide many possibilities for research, and staff is always available at the Reference Desk to help you. Some resources can be accessed remotely.
If your building is in the Chicago Historic Resources Survey, some of your research may already be done.
The Chicago Landmarks Commission has created a step-by-step guide to researching buildings.
The Cook County Assessor's website often shows a photograph of the property as it looks today. You can start with the Cook County Property Tax Portal. Search by address.
The Historic American Buildings Survey (HABS) documents structures throughout the U.S. with measured drawings, photographs, and data sheets. If you are looking for a prominent building, such as the Chicago Water Tower or the Marquette Building, you may find information here.
For many of Chicago's notable buildings, there are entries in the Clipping Files. Newspaper articles, dating from the 1930s through the 1980s, may add information not easily found online.