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§ 02
When a permit is required
Permit triggers and exempt work for LaSalle County
Any building, accessory structure, structure, deck, rebuilding, structural alteration, addition, relocation, or significant change of use in unincorporated LaSalle County if the structure is 200 sf or larger or has a side 20 feet or greater
Structures under 200 sf and with no side greater than 20 ft
Sidewalks, driveways, patios, window replacement, siding replacement, reroofing, soffits, gutters
Structures inside a corporate city or village boundary are not county permit work
Bona fide agricultural structures are exempt from county building code inspections, but not from code compliance or plumbing inspections
- Exempt Structures under 200 sf and with no side greater than 20 ft
- Exempt Sidewalks, driveways, patios, window replacement, siding replacement, reroofing, soffits, gutters
- Exempt Structures inside a corporate city or village boundary are not county permit work
- Exempt Bona fide agricultural structures are exempt from county building code inspections, but not from code compliance or plumbing inspections
Required documents
- Application, two copies of construction documents, site diagram, approved well permit, approved septic permit, and zoning-related approvals as applicable
- Building code
- County brochure says residential work follows IRC 2024 and NEC 2023 as amended by the County Board; non-agricultural commercial and multi-family work follows IBC 2024 plus IFC, IMC, IFGC, IEBC, IECC 2024 and NEC 2023 as amended by the County Board. This appears to be the county's published local adoption and should be read alongside the statewide 2025 mandate
- Contractor requirements
- Plumbing contractors must have a state license number to be registered; electricians and plumbers are state licensed under Illinois law
§ 03
Application process
Typical processing: Apply at least 30 days in advance; inspections are scheduled with 48 hours lead time
- 01 Confirm the work is in unincorporated LaSalle County and is not exempt.
- 02 Assemble the application packet, site diagram, construction documents, and any health department approvals.
- 03 Submit to the Land Use Department at least 30 days before anticipated construction.
- 04 County review by a building inspector.
- 05 Inspector notifies applicant when the permit is ready to pick up and the fee is known.
- 06 Pay the permit fee to the County Treasurer and receive the issued permit.
Typical processing time: Apply at least 30 days in advance; inspections are scheduled with 48 hours lead time
Source: LaSalle County Environmental Services and Land Use Department ↗
§ 04
Fee schedule
LaSalle County building permit fees
Fee type
Amount
01
Minimum permit fee
$25 agriculture exemption application fee; building permit fee itself is inspector-calculated from the ordinance schedule
02
Plan check fee
Included in inspector review process; no separate published plan check fee found
03
Permit fee formula
Square footage and number of inspections for detached 1-2 family dwellings; other work uses the ordinance fee schedule
04
Reinspection fee
Construction before permit issuance is subject to double the permit fee and each day is a separate offense
Fees change periodically. Confirm at the official fee schedule ↗ before budgeting.
§ 05
Required inspections
Scheduling and sequence
How to schedule
- Call 847-510-4104 (phone)
- Inspection hours
- County brochure says allow 48 hours for scheduling; inspector office hours 8:00-10:00 AM Monday, Wednesday, Friday
Failure to comply can delay occupancy and county notes that occupancy permits will not issue without well and septic certification
§ 06
Frequently asked
Common questions about unincorporated LaSalle County permits
01 Do I need a building permit in unincorporated LaSalle County, IL? ▸
Any building, accessory structure, structure, deck, rebuilding, structural alteration, addition, relocation, or significant change of use in unincorporated LaSalle County if the structure is 200 sf or larger or has a side 20 feet or greater
02 How much does a building permit cost in unincorporated LaSalle County, IL? ▸
Building permit fees in unincorporated LaSalle County, IL are set by the local building department and vary by project type and valuation. The minimum permit fee is $25 agriculture exemption application fee; building permit fee itself is inspector-calculated from the ordinance schedule. Fees are calculated as: Square footage and number of inspections for detached 1-2 family dwellings; other work uses the ordinance fee schedule. Plan check fee: Included in inspector review process; no separate published plan check fee found.
03 How do I apply for a building permit in unincorporated LaSalle County, IL? ▸
To apply for a building permit in unincorporated LaSalle County, IL, follow these steps: 1. Confirm the work is in unincorporated LaSalle County and is not exempt. 2. Assemble the application packet, site diagram, construction documents, and any health department approvals. 3. Submit to the Land Use Department at least 30 days before anticipated construction. 4. County review by a building inspector. 5. Inspector notifies applicant when the permit is ready to pick up and the fee is known. 6. Pay the permit fee to the County Treasurer and receive the issued permit.
04 How long does it take to get a building permit in unincorporated LaSalle County, IL? ▸
Building permit processing times in unincorporated LaSalle County, IL typically run Apply at least 30 days in advance; inspections are scheduled with 48 hours lead time. Timelines can vary based on project complexity and current department workload.
05 What work is exempt from building permits in unincorporated LaSalle County, IL? ▸
Not all construction work requires a permit in unincorporated LaSalle County, IL. The following work is generally exempt: Structures under 200 sf and with no side greater than 20 ft; Sidewalks, driveways, patios, window replacement, siding replacement, reroofing, soffits, gutters; Structures inside a corporate city or village boundary are not county permit work; Bona fide agricultural structures are exempt from county building code inspections, but not from code compliance or plumbing inspections. When in doubt, confirm with the local building department before starting work.
06 How do I schedule a building inspection in unincorporated LaSalle County, IL? ▸
Once your permit is issued and work reaches an inspection milestone, you can schedule a building inspection in unincorporated LaSalle County, IL via: Call 847-510-4104.
last verified April 2026
source LaSalle County Environmental Services and Land Use Department ↗
entry id permits/illinois/lasalle/unincorporated
Educational reference. Permit rules and fees change — confirm current requirements directly with LaSalle County Environmental Services and Land Use Department before applying. Jaspector is not legal advice.