ADU / Guest House Permit Requirements in Arlington Heights, IL
Village of Arlington Heights. Tyler EnerGov Civic Access Portal for online permits.
When you DO need a permit
Detached ADUs (new separate structures) require full building permits including electrical, plumbing, and mechanical. Check with your planning department for zoning approval and size limits.
Estimated fee: $1,000 – $5,000
Typical timeline: About 6 weeks
Source: Illinois Building Code / 2021 IRC with local amendments
Converting an existing space (garage, basement, or other area) to an ADU requires building, electrical, and plumbing permits. The conversion must meet all residential building code requirements for habitable space including egress, insulation, ceiling height, and ventilation.
Estimated fee: $500 – $3,000
Typical timeline: About 4 weeks
Source: Illinois Building Code / 2021 IRC with local amendments
Attached ADUs (additions to the existing house) require full building permits including all trades. This is treated as a room addition with the additional requirement of meeting ADU-specific zoning rules for independent living space.
Estimated fee: $800 – $4,000
Typical timeline: About 5 weeks
Source: Illinois Building Code / 2021 IRC with local amendments
ADU / Guest House Permit Costs: Arlington Heights vs. Nearby
Arlington Heights comes in on the low side for Illinois. You're looking at $500 – $5,000 here, compared to the state average of $766 – $4,000.
| City | Estimated Fee |
|---|---|
| Arlington Heights | $500 – $5,000 |
| Chicago | $1,000 – $5,000 |
| Chicago | $500 – $3,000 |
| Chicago | $800 – $4,000 |
Fees shown are estimates based on local building code data. Actual fees may vary based on project scope and valuation.
Zoning & HOA Considerations
ADU regulations vary dramatically by state and city. Many states (CA, OR, WA) have preemption laws that override local zoning restrictions. Check both state law and local zoning before designing.
If you live in an HOA community: hOAs have traditionally restricted ADUs, but state preemption laws in CA, OR, WA, and other states now limit HOA authority over ADUs. Check your state's ADU laws — your HOA may not be able to block construction even if CC&Rs appear to prohibit it.
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Frequently Asked Questions
Estimated permit fees for ADU / Guest House projects in Arlington Heights, IL range from $1,000 – $5,000. Fees vary based on project scope and valuation.
It depends on the specifics of your project. Some smaller ADU / Guest House projects may be exempt from permit requirements, while larger ones typically require a permit. Use our free lookup tool to check your specific situation.
Working without a required permit in Arlington Heights can result in fines, stop-work orders, being required to remove completed work, and complications when selling your home. It's always best to check first.
Typical approval time for ADU / Guest House permits in Arlington Heights is About 6 weeks. More complex projects may take longer if plan review is required.
If you live in an HOA community, you may need architectural review approval in addition to a building permit. HOA rules and city building codes are separate — you may need to satisfy both. Review your CC&Rs and submit to your HOA's architectural review committee before starting work.
Learn More About ADU / Guest House Permits
Read our complete guide covering permit requirements, costs, common exemptions, and the application process.
Read ADU / Guest House Guide →