04/10/2025

Legislative Alert: Support HB 1813 – Accessory Dwelling Units

If passed, HB 1813 would legalize the construction of accessory dwelling units (ADUs) and would limit local zoning decisions governing ADUs. APA-IL supports fiscal stability and sustainability at the local level, and this bill would encourage modest housing growth across the state leading to increased local revenues.

Step #2": Email your legislators and let them know they should SUPPORT HB 1813.

Editor’s Note: this page has been edited 4/11/25 to reflect that ADU occupancy under HB 1813 is not limited to two people or less.

Original Sponsor: Rep. Robert Rita (D. 28th District)

Status: On January 18, 2025, House Bill 1813 was introduced in the Illinois House, and on March 20, 2025, it passed out of the Housing Committee. Has had a second reading on house floor.

Summary: Creates new law that allows ADU construction and use statewide.

APA-IL supports House Bill 1813 for the following reasons:

APA-IL supports fiscal stability and sustainability at the local level. Under HB 1813, ADUs are typically occupied by no more than two people, and HB 1813 allows for gentle density to be added to residential zoning districts is expected to lead to modest population growth to residential areas that will not overly burden existing infrastructure. Thus, this bill will support maximizing existing infrastructure over expanding into undeveloped territory which aligns with APA-IL’s legislative priorities.

Further, the construction of new ADUs is expected to provide an increase in property values that will, in turn, lead to increased local tax revenue. According to a study by the Federal Housing Finance Agency examining property values of single family homes with and without ADUs in California, where ADUs have been legalized statewide since the mid-2010s, appraisal data showed homes with ADUs were more valuable and had values that grew at a higher rate over time than homes without ADUs. Further research has shown ADUs do not have a negative impact on properties that neighbor ADUs. Increases in aggregate property values support local fiscal sustainability.

Although it is a bill that would preempt local zoning authority, including home-rule municipalities, as stated above, ADUs are restricted to primary residences and are typically used by no more than two people. Additionally, the bill allows for municipalities to provide “reasonable regulations” regarding siting and location of ADUs in a similar fashion to the regulation of other accessory uses. Thus, the housing to be added will not be at a scale that disturbs existing zoning districts, and municipalities will be able to uniformly regulate ADU development. Ultimately, this bill preserves significant local control for municipalities to exercise their zoning power.

HB 1813 is a strong first step in addressing housing access and affordability at a statewide level.

Why you should SUPPORT this bill:

Guided by APA-IL's 2025 Legislative Priorities, APA-IL asks members to SUPPORT HB 1813. This bill meets a demonstrated need for additional housing, preserves some authority for local governments minor flexibility to regulate ADUs in their jurisdiction, promotes fiscal sustainability, and encourages gentle population growth statewide.

Recommendation: Contact your state legislators to SUPPORT HB 1813.