Unincorporated Jo Daviess County, Illinois requires a permit before construction or excavation, including new houses, most accessory buildings, decks, structural work, wiring and plumbing1. County zoning applies to all property outside a municipality2. If the land needs septic, obtain the county Health Department's septic permit or sign-off before Planning & Development can issue the building permit34.
At a glance
- Building permit
- Required before construction or excavation1
- Zoning
- County zoning applies outside incorporated municipalities25
- Septic permit
- Required for new and replacement systems; county Health Department approval comes before the building permit64
- Small accessory structure
- Under 120 sq ft needs no building permit if it has no electrical or plumbing, but zoning setbacks still apply3
- RV or tiny-home living
- County occupancy rules could not be confirmed; ask Planning & Development before buying or placing a unit2
- Owner-builder
- No exemption from the building permit or inspections could be confirmed; ask Planning & Development7
- Private well
- A state permit is required before construction, modification or sealing; ask the Health Department where to file locally8
- Permit review
- Approximately 15–20 working days after a complete application packet is received9
Who to call
Building permits
Jo Daviess County Planning & Development
Building permits, zoning certificates, occupancy certificates, plan review, construction inspections, unincorporated-area addresses and floodplain administration support
Highway Dept Building 1 Commercial Drive Suite 1 Hanover, IL 61041
Septic permits
Jo Daviess County Health Department
Septic permits and sign-offs required before issuance of a county building permit
9483 Route 20 West, Galena, IL 61036
Roads & driveways
Jo Daviess County Highway Department
County highways and county-road right-of-way work; ask whether the proposed access is under county, township or state jurisdiction
Highway Dept Building 1 Commercial Drive Suite 3 Hanover, IL 61041
Contact details are copied from each office’s official page and were checked against it on September 27, 2026.
Do you need a building permit in Jo Daviess County, Illinois?
Yes. Jo Daviess County requires a permit before construction or excavation, covering a new house, accessory building, deck, structural alteration or repair, electrical wiring, plumbing, and work governed by life-safety codes3. An accessory structure under 120 square feet is exempt only when it has no electrical or plumbing; zoning setbacks still apply3. The county adopted updated technical codes effective in 2025, including residential, building, mechanical, fuel-gas, plumbing, energy, accessibility and electrical codes10. Inspections are required for permitted work, and the owner or contractor must arrange them with Planning & Development as construction progresses11. Starting before permit issuance is costly as well as risky: the published schedule says fees for premature work may increase by 100 percent12.
Who issues Jo Daviess County building permits, and how do you reach them?
Jo Daviess County Planning & Development administers the county building code and zoning ordinance, reviews plans, issues building and zoning approvals, and inspects work under construction13. Reach the office at 815-591-3810 or [email protected], or visit the Highway Department Building at 1 Commercial Drive, Suite 1, Hanover, Illinois 6104113. The same department issues addresses in unincorporated Jo Daviess County and assists the Floodplain Officer with the floodplain ordinance13. The published fee schedule lists a $75 base application fee plus $4 per $1,000 of construction value, with $50 for an additional inspection; confirm the current amount before paying because the county materials carry differing revision labels12.
Does Jo Daviess County have zoning?
Yes. Every parcel outside an incorporated municipality is subject to Jo Daviess County zoning; land inside a city or village falls outside that county zoning scope5. Confirm the parcel's zoning district with Planning & Development rather than relying on the countywide map for a site decision, because the published map says it is for general planning and not site-specific analysis14. Road setbacks depend on the road authority, while Agricultural and R-1 districts have 20-foot side and 40-foot rear setbacks15. The county also limits impermeable lot coverage by zoning district16. A split creating lots smaller than 5 acres, or creating a new access easement, can trigger subdivision review17. Minimum home size, district-specific minimum lot size, building height, and the operative scope of the agricultural exemption could not be confirmed; ask Planning & Development for the rules tied to the parcel's district2.
How do septic permits work in Jo Daviess County?
The Jo Daviess County Health Department reviews plans, issues permits and inspects new and replacement private septic systems18. Every septic system must be permitted and may be installed by a licensed contractor or the homeowner, but installation is inspected for location, sizing, state-code compliance and county-ordinance compliance419. Obtain the septic permit or sign-off before the building permit can be issued3. Only 20.3% of county soils are rated without severe limits for a conventional drain field, so make the soil investigation an early feasibility item rather than assuming a standard system will fit20. The Health Department does not require a septic evaluation for every real-estate transaction, although a lender or purchase contract may require one19.
Can you live in an RV or tiny home on land in Jo Daviess County?
Jo Daviess County's reviewed materials do not give a complete answer for long-term RV occupancy, temporary camping or tiny-home occupancy. Because county zoning applies throughout unincorporated Jo Daviess County, ask Planning & Development whether the parcel's district allows the proposed use and what building, setback and sanitation approvals attach to it5. Do not treat a small structure as automatically habitable: the building-permit exception is limited to an accessory structure under 120 square feet with no electrical or plumbing, and zoning setbacks still apply3. Illinois approves several off-grid human-waste options, including privies and composting toilets, subject to detailed state requirements, while other domestic wastewater still needs a conventional private sewage disposal system21. Ask the Health Department to approve the sanitation plan before placing or occupying a unit18.
Building a home in Jo Daviess County: what are the steps?
- Confirm that the parcel is outside a municipality, then ask Planning & Development for its zoning district, allowed use, setbacks and lot-coverage limit51516.
- Confirm safe road access and the correct road authority; county materials direct applicants to the County Highway Department, township road commissioner or Illinois Department of Transportation as appropriate22.
- Complete septic review first, because a county septic permit or sign-off must precede the building permit4.
- Submit the complete building packet, including the value estimate, checklist, scaled plans, survey or site plan, and septic approval9.
- Allow approximately 15–20 working days after the complete packet arrives, pay the fee, and do not begin excavation early9.
What should you check before buying land in Jo Daviess County?
Start with buildability, not the listing description. Verify municipal status and the county zoning district, then have Planning & Development confirm the proposed home, setbacks, lot coverage and any subdivision issue517. Investigate septic early because only 20.3% of county soils are rated without severe conventional-drain-field limitations20. Check road ownership and access approval before choosing a driveway location; a driveway onto a state-maintained highway requires an Illinois Department of Transportation permit before work starts2224. Determine whether the building site is vulnerable to floodwaters, because the county requires a drawing-based elevation certificate before the building permit and a finished-construction certificate before an occupancy permit for affected projects23. For a private well, Illinois requires a permit before construction, modification or sealing8.
Watch-outs
- A county septic permit or sign-off must be issued before Planning & Development can issue the building permit3.
- Do not use the general county zoning map as a parcel determination; the map itself says it is not intended for site-specific analysis14.
- RV occupancy, tiny-home occupancy, temporary camping and a numeric minimum dwelling size remain unconfirmed; ask Planning & Development about the parcel's zoning district before committing to a purchase2.
- Projects vulnerable to floodwaters need elevation documentation before building and occupancy approvals23.
Sources
- Building Permit Requirements (2026 county census)
- Zoning FAQs (2026 county census)
- Building Permit Requirements, quoted and re-checked
- Private Sewage Disposal, quoted and re-checked
- Zoning FAQs, quoted and re-checked
- Private Sewage Disposal (2026 county census)
- (2026 county census)
- 77 Ill. Admin. Code 920.130, Water Well Permit Requirements (Illinois statewide rule), quoted and re-checked
- Building Permit Requirements and Process, quoted and re-checked
- Adopted Building Codes, quoted and re-checked
- Required Building Inspections, quoted and re-checked
- Planning and Development Fee Schedule, quoted and re-checked
- Jo Daviess County Planning & Development (jodaviesscountyil.gov)
- Official Zoning Map, quoted and re-checked
- Setbacks and Lot Coverage, quoted and re-checked
- Setbacks and Lot Coverage, quoted and re-checked
- Planning & Development, quoted and re-checked
- Private Sewage Disposal, quoted and re-checked
- Private Sewage Disposal, quoted and re-checked
- Share of soils without severe limits for a conventional septic drain field (USDA SSURGO): Bolthole Index county data
- 77 Ill. Adm. Code 905.130 Human Waste Disposal (Illinois statewide rule), quoted and re-checked
- Building Permit Requirements, quoted and re-checked
- Flood Hazard Areas, quoted and re-checked
- Highway Permits (Illinois statewide rule), quoted and re-checked
Written September 27, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.