Unincorporated Monroe County, Illinois requires building permits for covered construction, additions and structural alterations, and the county has zoning.12 The Monroe County Zoning Office issues building and electrical permits, handles zoning and flood zoning, and offers online applications through Cloudpermit.3 Private septic installation or repair requires a permit from the Monroe County Health Department.4
At a glance
- Building permit
- Required for covered construction1
- Zoning
- County zoning applies in unincorporated areas5
- Septic
- County permit required before installation or repair4
- RV living
- Not confirmed; temporary use needs written permission unless specifically allowed6
- Tiny home
- Classification must be confirmed; residential minimum is generally 900 square feet7
- Owner-builder
- No exemption confirmed8
- Private well
- State or approved local permit required before work9
Who to call
Building permits
Monroe County Zoning & Building
Building and electrical permits, zoning, flood zoning, appeals and code enforcement
100 S. Main St., Waterloo, IL 62298
Septic permits
Monroe County Health Department — Environmental Health
Environmental health questions involving private sewage disposal and wells
1315 Jamie Lane, Waterloo, IL. 62298
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 Monroe County, Illinois?
Yes. Unincorporated Monroe County requires a permit for covered nonagricultural construction, additions and structural alterations.10 Agricultural buildings are not a blanket exception: the county material identifies a permit trigger for agricultural buildings or structures exceeding $500 in cost or 100 square feet, but the complete provision should be checked for its exceptions.10
New-home construction requires 10 inspections, with the building inspector determining the inspection schedule; the published inspection charge is $70 per inspection.11 Before a regulated structure, use or lot is occupied or operated, the county requires a final certificate of zoning compliance after inspection confirms the approved work was completed as planned.12
Who issues building permits in Monroe County, Illinois?
Monroe County Zoning & Building is the permit office for unincorporated land; its official page says the office issues building and electrical permits and handles zoning, flood zoning, appeals and code enforcement.3 Reach the office at 618-939-8681 ext. 260 or visit 100 S. Main St., Waterloo, IL 62298.3
Applicants may apply and track a building permit online through Cloudpermit, including requesting inspections and receiving results by email.3 Paper forms can instead be submitted by email or dropped off at the Zoning Office.3 The published building-permit fee is $5 per $1,000 of structure value, plus $70 for each inspection.13
Does Monroe County, Illinois have zoning?
Yes. The county zoning code applies throughout unincorporated Monroe County, and its zoning articles also apply inside municipalities that have not adopted their own zoning code.5 A municipality with its own zoning code follows that municipal code instead, so confirm whether a parcel lies inside municipal limits before relying on county rules.14
Lot area, dimensions, setbacks and height depend on the zoning district.151617 Residences generally need at least 900 square feet of living area, although district-specific provisions can apply.7 Agricultural buildings must still meet district setbacks, and county provisions apply to any part of a tract that stops being used solely for agriculture.18
How do septic permits work in Monroe County?
The Monroe County Health Department regulates private sewage disposal for residences and facilities not served by public sewer.19 A permit is required before installing or repairing a private sewage system, and the department reviews applications against state health requirements and the county private sewage ordinance.4 Call Environmental Health at 618-939-3871 ext. 212 or email [email protected] before designing the system.20
Only 11.6% of county soils are rated without severe limitations for a conventional septic drain field, so septic feasibility deserves early site work.21 The department also offers property-transfer or loan inspections for $200 after an application is completed.22
Can you live in an RV or tiny home in Monroe County?
Do not assume an RV can serve as a residence on unincorporated land. Monroe County requires written permission before land or a temporary structure is used for a temporary purpose unless the zoning code specifically allows it, while private recreation areas or camps are special uses in the Agricultural District.6 Ask Zoning & Building how the parcel's district treats the proposed RV use before moving in.3
The county code does not define or resolve tiny-home occupancy as a separate category. Manufactured homes have their own district, lot, foundation and anchoring conditions, while residences generally require at least 900 square feet of living area.237 Residential use of an accessory building is prohibited under the reviewed provision.24
Building a home in Monroe County: what are the steps?
- Confirm whether the parcel is unincorporated and identify its zoning district, because county and municipal zoning jurisdiction can differ.14
- Ask Zoning & Building to confirm lot area, setbacks, access and flood constraints before finalizing a site plan.151625
- Have Environmental Health evaluate the private sewage proposal before construction where public sewer is unavailable.19
- Submit the building application through Cloudpermit or by email or drop-off at the Zoning Office.3
- Obtain approval for the driveway entrance from the road's legal maintenance authority; the County Engineer approves county Highway Entrance Permits.26
- Schedule the required inspections and obtain the final certificate of zoning compliance before occupancy.1112
What should you check before buying land in Monroe County?
Start with jurisdiction, zoning district, legal access, septic feasibility, water and flood exposure. County zoning applies to unincorporated land, while a municipality may have its own code.14 A driveway entrance needs approval from the roadway's maintenance authority, and work in a state-highway right-of-way requires an IDOT permit before work starts.2627
For a private well, Illinois requires a permit from the state or an approved local health department before construction, modification or sealing begins.9 Flood-hazard construction is reviewed for flood safety and must meet protective design requirements.25 The county's effective property-tax rate is about 1.7%, and the median annual property-tax bill is $4,523.2829
Watch-outs
- An owner-builder exemption was not confirmed in the reviewed county materials; ask Zoning & Building before assuming self-performed work changes permit requirements.83
- Tiny-home classification and occupancy remain unconfirmed, so get a written parcel-specific determination from Zoning & Building before purchase.3
- Only 11.6% of Monroe County soils are rated without severe limitations for a conventional septic drain field.21
Sources
- Monroe County Code of Ordinances (2026 county census)
- Chapter 40 Zoning Code (2026 county census)
- Monroe County Zoning & Building (monroecountyil.gov)
- Private Sewage Disposal Systems, quoted and re-checked
- Chapter 40 Zoning Code, quoted and re-checked
- Chapter 40 Zoning Code, quoted and re-checked
- Chapter 40 Zoning Code, quoted and re-checked
- (2026 county census)
- 77 Ill. Admin. Code 920.130, Water Well Permit Requirements (Illinois statewide rule), quoted and re-checked
- Monroe County Code of Ordinances, quoted and re-checked
- Application for Building Permit, quoted and re-checked
- Chapter 40 Zoning Code, quoted and re-checked
- Fee Schedule, quoted and re-checked
- Zoning & Building, quoted and re-checked
- Chapter 40 Zoning Code, quoted and re-checked
- Chapter 40 Zoning Code, quoted and re-checked
- Chapter 40 Zoning Code, quoted and re-checked
- Chapter 40 Zoning Code, quoted and re-checked
- Private Sewage Disposal Systems, quoted and re-checked
- Monroe County Health Department — Environmental Health (monroecountyhealth.org)
- Share of soils without severe limits for a conventional septic drain field (USDA SSURGO): Bolthole Index county data
- Private Sewage Disposal Systems, quoted and re-checked
- Chapter 40 Zoning Code, quoted and re-checked
- Chapter 40 Zoning Code, quoted and re-checked
- Monroe County Code of Ordinances, quoted and re-checked
- Monroe County Code of Ordinances, quoted and re-checked
- Highway Permits (Illinois statewide rule), quoted and re-checked
- Effective property tax rate: Bolthole Index county data
- Median property tax bill: Bolthole Index county data
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.