Accessory Structures in Downers Grove, IL (2026)
1 verified accessory structures rules for Downers Grove, Illinois, sourced directly from the municipal code and official government pages.
Verified from official government sources
Garage Conversions
Downers Grove single-family lots may have total building coverage (house + attached garage + accessory buildings) of up to 32% of the lot, with the combined size of all accessory structures capped at the lesser of 1,000 square feet or the size of the primary house. Accessory structures cannot exceed 23 feet to the highest point, and detached garages of 500 sq ft or less on lots 60 feet wide or narrower don't count toward building coverage.
Building a Garage in Downers Grove, IL — Size & Permit Rules
Some RestrictionsLooking for DuPage County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Downers Grove city rules.
Accessory Structures in DuPage County →