Illinois Tiny Homes Law: Statewide Accessory Structures Rules (2026)

Key Facts

Code Authority: Capital Development Board
Manufactured Homes: 430 ILCS 115
RV Classification: 625 ILCS 5
Foundation Required: For permanent dwellings

Full Breakdown

The Capital Development Board Act (20 ILCS 3105) and the Illinois Building Commission Act (20 ILCS 3918) authorize statewide minimum construction standards. The state has adopted the International Residential Code as the baseline; tiny homes on foundations must meet IRC Appendix Q (300 sq ft minimum standards) where adopted, and manufactured tiny homes must comply with HUD code under 430 ILCS 115. RVs and park-model trailers fall under 625 ILCS 5 vehicle titling rules. Local zoning may impose minimum dwelling sizes.

Violations & Penalties

Construction without code compliance can result in stop-work orders, denial of certificates of occupancy, and civil penalties under the Illinois Building Code.

Frequently Asked Questions

Are tiny homes legal dwellings in Illinois?

Tiny homes on permanent foundations meeting the Illinois-adopted IRC are legal dwellings statewide, but local zoning can impose minimum lot sizes or square footage requirements.

Can I live full-time in a tiny home on wheels in Illinois?

Tiny homes on wheels are classified as recreational vehicles under 625 ILCS 5 and generally cannot be used as permanent dwellings outside of licensed RV parks.

Illinois Building Code Applies to Tiny Home Construction Statewide

Key Facts

Full Breakdown

Violations & Penalties

Frequently Asked Questions

Sources

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