It’s possible to use 1950 U.S. Census records to establish a number of historic dwelling units at a building in Chicago for the purposes of the city generating a “zoning certificate”. That’s a recognition of the number of legal dwelling units especially useful when that number of dwelling units is greater than the current zoning code allows. They’re required to be generated (i.e. requested from the city’s planning department) during the sale of a small-scale residential property.

This Chicago zoning certificate was generated the “normal” way (which I don’t know how to describe), while this blog post is about digging up evidence in case the normal way doesn’t affirm the number of dwelling units you want it to affirm.

However, based on a recent experience of a client of mine, the zoning certificate – while supposedly valid for one year – is subject to dispute later! Finding Census records showing the same or more dwelling units in a given building has helped re-establish the validity of the number of units stated in a zoning certificate.

It will take you some time to research Census records! (I would budget at least one hour. There is a painstaking process to find the webpage that has the enumeration (counting) sheets for the address you want, and it will take some time to sift through those sheets (and you may have to look at multiple pages for the same address).

Here are the steps involved

  1. Find the enumeration district (ED).
  2. Go to that ED’s set of sheets in the National Archives 1950 Census website.
  3. Page through and read every sheet until the address is found.

Find the enumeration district

The New York Public Library has a great tutorial on their blog, and I recommend you start by reading section 2, Generate an ED number.

Once you locate the ED (following the instructions in Section 2) I would say stop reading the NYPL blog post.

Alternatively, for Chicago address lookups, you can browse these maps of the enumeration districts and then search for those ED numbers directly on the National Archives website.

Section 2 will advise you to use Steve Morse’s third-party Unified Census ED Finder (which is the most useful part of this process). The ED Finder has a wizard asking you to select state, county, city, and street name and cross street. It will then produce a set of one or more ED numbers under the heading, “1950 ED numbers corresponding to your location”.

A screenshot of the ED Finder “wizard”.

Tip: ED Finder will likely show you multiple ED numbers; you may need to look at all of them to find an address. I think this happens because the link between each enumeration district and a city’s streets is imprecise

Click each ED number, which opens a new tab in the ED Finder website with links to three different image viewers. These are databases where scans of microfilm are shown online. One of them, NARA, is public – that’s the National Archives & Records Administration. I recommend that one as it’s free and doesn’t require an account.

Read each enumeration sheet

Once you arrive on the NARA website click on the “Population Schedules” to reveal the enumeration sheets. Start paging and reading!

Tip: Street names are written vertically on the left edge of the page.

A screenshot of the 1950 Census database and website of NARA. It’s necessary to click the “population schedules” button to display the enumeration sheets.

The NARA viewer isn’t the best – it doesn’t allow you to make it full-screen; I was constantly having to zoom in to read the street names and house numbers.

A screenshot of a 1950 Census enumeration sheet with two annotations.