There are many questions that can be answered and stories to explore each time we update the Cook County property data (which is done annually, as explained last week). For example, “How many two-flats were lost?”
The answer? From 2017 to 2018, there was a decrease of approximately 1,346 two-flats in all of Cook County. It’s possible some were demolished, deconverted to single-family houses, or burned down, while others may have gotten a third unit to become a three-flat.
Transforming vacant land
The question that I wanted to answer was how many vacant lots were redeveloped in Chicago. I looked through Chicago Cityscape’s huge Cook County property database for Chicago properties that the Cook County Assessor had classified as vacant in 2017 but not vacant in 2018. That query resulted in about 984 vacant parcels that had been redeveloped between 2017 and 2018. (It’s likely a little less than that because of errors in the data, and many parcels are combined in a single redevelopment project.)

The most common transformation patterns, by land area, were redeveloping vacant lots into industrial buildings, one-story commercial buildings, and apartment buildings with more than seven units.
By parcel count, though, the plurality of vacant lots — about 154 of them — were developed into single-family houses. Hotspots were in Washington Heights, McKinley Park and Bridgeport, and Forest Glen.






