Unincorporated Lee County, Illinois requires a county building permit for structures through its Building and Zoning Office.1 County zoning also controls permitted uses and where improvements may sit, while the Lee County Health Department permits and inspects private septic systems.23
At a glance
- Building permit
- Required for structures in unincorporated Lee County; use the county portal14
- Zoning
- Yes; allowed uses depend on the parcel's county zoning district25
- Septic
- Lee County Health Department permit and inspection required36
- Private well
- Lee County Health Department permit required for a new well7
- RV living
- Not confirmed; ask Building and Zoning about the parcel and proposed occupancy8
- Tiny home
- No countywide occupancy answer confirmed; zoning and permit review still apply21
- Owner-builder exemption
- Not confirmed by the county's published permit materials9
- Floodplain work
- Development is restricted and may require county and state review1011
Who to call
Building permits
Lee County Building and Zoning Office
Building permits and permit questions for construction in unincorporated Lee County; the broader office also administers zoning, subdivision and floodplain inquiries
Septic permits
Lee County Health Department, Environmental Health
Private sewage disposal permits and inspections, new-well permits, and sanitary evaluations in Lee County
309 S. Galena Ave., Ste. 100, Dixon, IL
Roads & driveways
Driveway-access, culvert and drainage questions for roads under county jurisdiction
1629 Lee Center Road, Amboy, IL 61310
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 Lee County, Illinois?
Yes. A structure in unincorporated Lee County generally goes through the county building-permit process; the county separates fence, pool, commercial, portable-shed and other application paths.1 The general building application calls for an application, a site plan and architectural plans, along with the parcel number and zoning.4 Apply online, but do not treat the submission notice or assigned permit number as permission to start: work may begin only after the county provides an approved placard and approval letter.4
Lee County describes itself as having no county building code, but its plan review uses current state and model standards including the applicable building, energy, accessibility, plumbing, fire and electrical codes.12 Illinois also has statewide baseline building-code requirements effective in 2025.13
Who issues building permits in Lee County, Illinois?
The Lee County Building and Zoning Office is the first stop for a project in an unincorporated area, and the county directs permit applicants to its online portal.8 Call the Building Official at 815-288-3109 or email [email protected] if the project category is unclear.8 The office says applicants can search and submit through its online system, and the general application requires the site plan and architectural plans in addition to the application itself.84
County permit fees are published rather than flat across every project: the reviewed schedule lists charges based on project type and floor area, with a minimum building-permit fee.14 Because the county page also identifies separate application paths, confirm the current category and amount before budgeting.1
Does Lee County, Illinois have zoning?
Yes. Unincorporated Lee County is divided into zoning districts, and each district controls allowed uses and the location of improvements.2 Lee County publishes its zoning regulations under Title 10, so a parcel's district is the starting point for questions about a house, accessory structure, business, setback or special use.5 Incorporated cities and villages may administer their own rules instead of county zoning.2
Do not assume one setback applies everywhere: Illinois leaves actual distances to the applicable zoning district, and the reviewed county figures cover commercial and industrial districts rather than every residential or agricultural parcel.1516 Certain agricultural uses may qualify for a state-law zoning exemption, but Lee County directs landowners to the Zoning Department for an eligibility decision.17
How do septic and well permits work in Lee County?
The Lee County Health Department issues permits and conducts inspections for private sewage systems installed in Lee County, and those systems must follow county and Illinois private-sewage codes.36 Illinois requires plan approval from the department or local authority before construction of a new private sewage system begins.18 Contact Environmental Health at 815-284-3371 or [email protected].19
Site conditions deserve attention before a purchase: only about 16% of Lee County soils are rated without severe limitations for a conventional septic drain field.20 That rating does not decide whether a particular parcel can support a system, but it makes early site evaluation especially useful. New private wells also require a Lee County Health Department permit.7 The same department can answer whether a proposed alternative sanitation setup meets county and state requirements.19
Can you live in an RV or tiny home in Lee County?
Lee County's published material does not give a confirmed countywide answer for living in an RV on private land, temporary camping, tiny-home occupancy, manufactured-home placement or accessory-dwelling occupancy. Ask the Building and Zoning Office about the parcel's district and the exact proposed use before buying or moving a unit onto the land.8 County zoning divides unincorporated land into districts with different permitted uses, so a use allowed on one parcel may need approval or be unavailable on another.2
A tiny home is not a way around the permit process: structures in unincorporated Lee County remain subject to the applicable building-permit path.1 Illinois rules allow manufactured homes as dwellings under stated installation requirements, but local zoning, building, floodplain and utility rules can still apply.21 No explicit owner-builder permit exemption was confirmed in the county's published material.9
Building a home in Lee County: what are the steps?
For a home on unincorporated land, use this order:
- Confirm the parcel number, zoning district, allowed residential use and parcel-specific setbacks with the Building and Zoning Office.42
- Ask the Lee County Health Department for preliminary septic and private-well review, then obtain the required permits and inspections.37
- Prepare the building application, site plan and architectural plans, and submit them through the county portal.4
- Resolve access with the road authority that controls the frontage; county commercial materials require driveway-access, address-sign and drainage approvals from the Highway Engineer after an address is issued.22
- If the site is in a flood hazard area, complete the county and any applicable state review before construction.1011
- Wait for the approved placard and approval letter before starting work.4
What should you check before buying land in Lee County?
Start with jurisdiction: confirm that the parcel is in unincorporated Lee County rather than a city or village with its own rules.2 Then verify the zoning district, allowed dwelling type, setbacks, access and whether a land division needs subdivision approval; the county regulates divisions of land in unincorporated areas.523
Check septic feasibility and the water source early because most mapped soils carry severe limitations for a conventional drain field, and new private wells require a permit.207 Review flood maps and ask the Building and Zoning Office whether county or state floodplain approvals apply.10 The typical farmland value is about $10,639 per acre, while the effective property-tax rate is about 1.9%; use parcel records and a current assessment rather than countywide figures for an offer.2425 Finally, confirm which road authority controls the frontage before designing a driveway.26
Watch-outs
- An online submission and permit number do not authorize construction; wait for the approved placard and approval letter.4
- Lee County has not published a confirmed countywide rule for private-land RV occupancy or tiny-home occupancy; ask Building and Zoning about the parcel and intended use.8
- Floodplain rules allow only limited development without a variation, and additional county or state approvals may be needed.10
- A driveway onto a state-maintained road requires an IDOT permit before work begins; county-road access questions go to the Lee County Highway Department.2627
Sources
- Building Permits | Lee County, IL, quoted and re-checked
- Zoning | Lee County, IL, quoted and re-checked
- Environmental Health | Lee County Health Department, quoted and re-checked
- Building Permits | Lee County, IL, quoted and re-checked
- Zoning | Lee County, IL, quoted and re-checked
- Environmental Health | Lee County Health Department, quoted and re-checked
- Environmental Health | Lee County Health Department, quoted and re-checked
- Lee County Building and Zoning Office (leecountyil.com)
- (2026 county census)
- Floodplain Information and Regulations | Lee County, IL, quoted and re-checked
- Permit Application and Instructions (Illinois statewide rule), quoted and re-checked
- BUILDING PERMIT FEES & REGULATIONS, quoted and re-checked
- Illinois Codes (Illinois statewide rule), quoted and re-checked
- BUILDING PERMIT FEES & REGULATIONS, quoted and re-checked
- 55 ILCS 5/5-12001 — Authority to regulate and restrict location and use of structures (Illinois statewide rule), quoted and re-checked
- COMMERCIAL BUILDING PERMIT REQUIREMENTS, quoted and re-checked
- Zoning | Lee County, IL, quoted and re-checked
- 77 Ill. Adm. Code 905.190 Installation Approval (Illinois statewide rule), quoted and re-checked
- Lee County Health Department, Environmental Health (lchd.com)
- Share of soils without severe limits for a conventional septic drain field (USDA SSURGO): Bolthole Index county data
- Manufactured & Modular Homes/Mobile Structures (Illinois statewide rule), quoted and re-checked
- COMMERCIAL BUILDING PERMIT REQUIREMENTS, quoted and re-checked
- Subdivision Regulations | Lee County, IL, quoted and re-checked
- Farmland value per acre (USDA census): Bolthole Index county data
- Effective property tax rate: Bolthole Index county data
- Highway Permits (Illinois statewide rule), quoted and re-checked
- Lee County Highway Department (leecountyil.com)
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.