Illinois 2025-2026 Regular Session

Illinois House Bill HB1709

Introduced
1/24/25  
Refer
1/28/25  
Refer
2/18/25  

Caption

LOCAL-ACCESSORY DWELLING UNITS

Summary

HB1709 creates the Local Accessory Dwelling Unit Act, a new state law governing accessory dwelling units (ADUs) in Illinois. The bill defines an accessory dwelling unit as an attached or detached residential unit on the same parcel as a primary residence, with independent living facilities, and expressly includes efficiency units and certain manufactured homes. It also defines an efficiency unit as a small unit for up to two people with at least 150 square feet and possibly partial kitchen or bathroom facilities. The core policy change is that local governments would be prohibited from banning the construction or use of ADUs. Municipalities and other units of local government could still adopt reasonable rules on size and location, similar to regulations for other accessory structures, but only so long as those rules do not effectively prevent ADUs. The bill also restricts home rule authority by making the Act a limitation on inconsistent local regulation, and it would take effect immediately if enacted.

Impact

HB1709 would preempt local zoning and land-use rules to the extent they prohibit accessory dwelling units, creating a statewide floor that requires local governments to allow ADUs. It would affect municipalities, counties, and other local governments, including home rule units, by limiting their ability to use local ordinances to block ADUs outright or through overly restrictive size and siting rules. The bill would likely influence housing policy, infill development, and the availability of smaller or secondary housing units on existing residential lots.

Sentiment

Based on the bill text and the absence of recorded committee debate or votes in the provided materials, the available sentiment appears generally supportive of expanding housing options and reducing local barriers to ADUs. The bill’s framing suggests a pro-housing, pro-affordability approach that favors statewide consistency over local restriction. Because there are no transcripts or vote records here, no formal opposition or support can be directly attributed from the legislative record provided.

Contention

The main point of contention is likely local control versus state preemption. Supporters would view the bill as necessary to prevent local bans and make it easier to add housing units, while opponents may argue it overrides municipal zoning authority and could affect neighborhood character, infrastructure, parking, or density. Another likely issue is how “reasonable regulations” and the prohibition on rules that have the effect of banning ADUs would be interpreted and enforced, since that language leaves room for disputes over what counts as an impermissibly restrictive ordinance.

Companion Bills

No companion bills found.

Previously Filed As

IL HB3552

LOCAL-ACCESSORY DWELLING UNITS

IL HB5626

MUNI CD-ACCESSORY DWELLINGS

IL HB1813

MUNI CD-ACCESSORY DWELLINGS

IL SB543

Accessory dwelling units and junior accessory dwelling units.

IL SB1117

Accessory dwelling units and junior accessory dwelling units.

IL SB3726

MUNI CD-ACCESSORY DWELLINGS

IL AB449

Local regulation of accessory dwelling units. (FE)

IL SB4071

MUNI CD-ACCESSORY DWELLINGS

IL SB473

Local regulation of accessory dwelling units. (FE)

IL HB4711

Accessory dwelling units

Similar Bills

TX SB673

Relating to municipal and county regulation of accessory dwelling units; authorizing a fee.

IL HB3552

LOCAL-ACCESSORY DWELLING UNITS

WV SB659

Prohibiting certain restrictions on regulation of accessory dwelling units

ID S1277

ACCESSORY DWELLING UNITS – Amends and adds to existing law to revise provisions regarding prohibitions against restrictive covenants banning accessory dwelling units and to establish provisions regarding accessory dwelling units in the Local Land Use Planning Act.

CA SB9

Accessory Dwelling Units: ordinances.

IA HSB162

A bill for an act relating to county and city regulation of accessory dwelling units.(See HF 947.)

IA SSB1182

A bill for an act relating to county and city regulation of accessory dwelling units.(See SF 592.)

ID S1354a

ACCESSORY DWELLING UNITS – Amends and adds to existing law to revise provisions regarding prohibitions against restrictive covenants banning accessory dwelling units and to establish provisions regarding accessory dwelling units in the Local Land Use Planning Act.