Illinois Tiny House Zoning Laws Overview
Illinois does not have a unified set of statewide tiny house laws. Each county and city sets its own rules on minimum square footage, foundation requirements, and where tiny homes can be placed. This means regulations vary widely across the state's 102 counties. For permanent tiny houses on foundations, local building codes apply. Most jurisdictions follow the International Residential Code (IRC) or International Building Code (IBC), which sets a minimum of 120-150 square feet for habitable dwellings. However, many Illinois municipalities enforce their own minimums, ranging from no requirement in rural areas to 900+ square feet in some suburban jurisdictions. Tiny houses on wheels are classified as recreational vehicles (RVs) in most Illinois jurisdictions. This means they are typically only allowed for permanent dwelling in RV parks, mobile home parks, or specific zones that permit RV living. Some rural, unzoned areas may have more flexibility. Many Illinois counties allow tiny homes as accessory dwelling units (ADUs) on existing properties. ADU regulations vary by location - some require special approval, while others allow them by right in certain zones. Cook, DuPage, Lake, and Will counties all have ADU provisions, though requirements differ. The practical approach in Illinois: Start by determining if your target location is incorporated (city/village rules apply) or unincorporated (county rules apply). Then contact the local building and zoning department to confirm minimum square footage, foundation requirements, and whether tiny homes on wheels are permitted.
Illinois has no statewide tiny house rules. This guide covers all 81 counties and cities. Regulations vary dramatically by county and city. Many rural counties are flexible, while suburban areas often have strict minimums. Always verify with local zoning before buying land.
Understanding the zoning laws is just the first step. Once you know what is legal in Illinois, you can start looking at tiny houses for sale in Illinois or connect with experienced Illinois builders who work within these regulations. If you want a turnkey solution, consider joining a tiny house community in Illinois where all the zoning and permits are already handled.
Before you buy land or start construction, use our zoning finder tool to check specific county requirements, and get a budget estimate with our free tiny house cost calculator. If you're planning to go off-grid, check out our comprehensive off-grid living guide to understand utility and septic requirements.
