As a property owner, it’s common to field questions about the legality of apartment units like those in a basement, attic, or coach house. Often, owners are unsure and default to “it was there when I bought the property.” But why does it matter if it’s a legal unit?

1. Value

The distinction between a legal apartment and an accessory unit influences the property’s value.  Legal apartments can be openly advertised and rented out, contributing to the property’s income potential.  Accessory units not recognized as legal dwellings may limit the owner’s ability to generate rental income legally, thereby impacting the property’s income potential and value.

2. Risk of Enforcement Actions

The existence of illegal units exposes property owners to the risk of fines, penalties, and mandatory alteration or removal of the unpermitted spaces. These potential costs and legal complications can affect the property’s value and attractiveness to buyers.

Applying for a Certificate of Zoning Compliance certifies the number of residential dwelling units at a property that are legal under the Chicago Zoning Ordinance.

A dwelling unit is defined as one or more rooms set up for a single household. Buildings with more than one kitchen are considered to have multiple dwelling units unless the extra cooking facilities are clearly accessory and not for additional households.

To get a Certificate of Zoning Compliance, submit your application at Room 107 of City Hall, 121 N. La Salle St., between 9 a.m. and 5 p.m., Monday through Friday. You’ll need to pay a $120 filing fee.

The following information is required:

  • The property address.

  • Property Index Number (PIN).

  • The number of dwelling units within the structure.

  • The location of the dwelling units by floor.

  • Owner applicant information.

  • Self-addressed and stamped envelope.

The Department of Planning and Development typically provides an initial decision within five business days after receiving an application.

If you’re selling or transferring residential property with five or fewer dwelling units in Chicago, a Certificate of Zoning Compliance is mandatory. However, this requirement doesn’t apply to condominiums or cooperative buildings.

To take the next steps, download the Certificate of Zoning Compliance Application: