Zoning, building permits and septic rules in Peru Township, Illinois

Rules another office applies inside Peru Township

Peru Township does not set these itself; the county, a health district or the state does, and they apply to every address inside its limits.

• Building permitRequired

  Construction, rebuilding, structural alteration, addition, relocation or significant change of use of structures inside Peru township outside the City of Peru limits, under the LaSalle County Building Permit Ordinance

  • Permit required for structures of 200 square feet or larger, or with a side of 20 feet or greater.
  • Construction beginning before permit issuance is subject to a penalty of double the permit fee, with each day a separate offense.
  • Agricultural buildings are exempt from county building code inspections (see agricultural_exemption claim).
  • Issuance of the county permit does not exclude compliance with other local, state or federal regulation.

  minimum structure size requiring permit: >= 200 square feet (or any structure with a side of 20 feet or greater)

  “Any…. Building, Accessory Structure, Structure, Deck, Rebuilding, Structurally Altering, Adding to, Relocation, or significant change of use, of structure in unincorporated LaSalle County If…. The Structure is one of the following: 1. 200 s.f. or larger or; 2. has a side of 20 feet or greater”

• Building code adoptedAdopted (with conditions)

  Building permit construction inside Peru township outside the City of Peru limits, under the LaSalle County Building Permit Ordinance (unincorporated LaSalle County)

  • Residential structures that require building permits are subject to the 2024 International Residential Code.
  • For one and two family dwellings, 2024 and 2023 national electric code as amended by the LaSalle County Board applies.
  • Non-agricultural commercial and multi-family buildings are subject to the 2024 International Building Code, International Fire Code, International Mechanical Code, International Fuel Gas Code, International Existing Building Code, International Energy Code and 2023 National Electrical Code as amended by the county board.
  • Brochure states the adopted building codes are available at codes.iccsafe.org.

  “Residential Structures that require Building Permits are subject to the International Residential Codes - for one and two family dwellings, 2024 and 2023 National Electric Code as amended by the LaSalle County Board.”

• InspectionsRequired

  Structures receiving a county building permit inside Peru township outside the City of Peru limits

  • Inspections scheduled by calling 847-510-4104 with about 48 hours' notice, per the brochure.
  • Agricultural buildings are exempt from county building code inspections but remain subject to Illinois Department of Public Health plumbing inspections (309-693-5360).

  “Building Code inspections will apply to all structures which receive Building Permits.”

• Zoning districtsPublished (with conditions)

  County zoning districts that apply to land inside Peru township outside the City of Peru limits

  • Zoning district maps are adopted by reference for each township of the county; the township map for Peru township was not opened.
  • Districts listed include A-1 agriculture, AC agriculture-conservation, R-1 rural residence (RR section 8.1), R-2 single family residence, R-3 general residence, B-1, B-2 business and I-1 industrial.

  “In order to carry out the purpose and intent of this Ordinance, the unincorporated area of the County is hereby divided into the following districts:”

• Minimum lot sizeSpecified

  Single-family detached dwelling in the RR rural residence district (sec. 8.1) of unincorporated LaSalle County, applying inside Peru township outside the City of Peru limits

  • Planned unit developments have no minimum lot area.
  • Lot width of at least 150 feet applies to all permitted or special uses in the RR district.
  • Lot size is set by the county zoning ordinance, not by a township ordinance.

  minimum lot area, single-family detached dwelling, RR district: >= 1 acre (planned unit developments have no minimum lot area)

  “1. Single Family Detached Dwellings: The zoning lot shall not be less than one (1) acre in size. 2. Planned Unit Developments: Minimum lot area not required.”

• Who permits septicCounty (with conditions)

  Private sewage disposal systems on land inside Peru township outside the City of Peru limits; the LaSalle County Health Department is the contact for the state-law private sewage code

  • The rule is the Private Sewage Disposal Licensing Act and Code, a state law administered locally; the brochure refers septic questions to the LaSalle County Health Department at 815-433-3366.
  • Septic approval is also a precondition to a county building permit under the Building Permit Ordinance (brochure).

  “Copy of approved Septic Permit from LaSalle County Health Department”

• Subdividing landRegulated (with conditions)

  Division of land inside Peru township outside the City of Peru limits, under the LaSalle County Subdivision Control Ordinance

  • Subdivision ordinance compliance must be met before a county building permit is issued (brochure).
  • Lots created by subdivision or deed division must make land/cash donations under the county subdivision control ordinance (zoning sec. 4.3-8).
  • Each lot resulting from a division must meet the district bulk regulations; corner lots must be 25 feet wider than the minimum lot width.

  “Such lots, created by subdivision or deed division, shall be required to make land/cash donations in accordance with the LaSalle County Subdivision Control Ordinance.”

• Driveway accessRequired

  Driveway and road access for lots inside Peru township outside the City of Peru limits, under the LaSalle County Highway Access Ordinance

  • Highway access ordinance must be met before a county building permit issues; contact the county highway department at 815-434-0743.
  • The excerpt does not state the access standards themselves; those were not opened.

  “LaSalle County Highway Access Ordinance For more information contact the LaSalle County Highway Department at 815-434-0743.”

• Building in a floodplainRequired

  Development in floodplain areas inside Peru township outside the City of Peru limits, under the LaSalle County Floodplain Ordinance

  • Floodplain ordinance compliance must be met before a county building permit issues; the floodplain ordinance text was not opened.
  • Applies only where a parcel is within a mapped floodplain.

  “In addition to the LaSalle County Building Permit Ordinance, the following County Ordinances must be met before the issuance of a building permit: ------------------- Subdivision Ordinance Floodplain Ordinance”

• Permit feesVariable (with conditions)

  County building permit fees for construction inside Peru township outside the City of Peru limits

  • Fee is set after the building inspector reviews plans; fees are nonrefundable and paid on pickup.
  • Fee schedule for nonagricultural one and two family dwellings is in Article 6 of the county building permit ordinance (based on square footage and number of inspections).
  • A 2025 county fee schedule PDF exists on the county site but was not opened; it may be superseded.

  “For nonagricultural detached one and two family dwellings not more than three stories in height and/or their accessory structures, fees are based on square footage of structure and the number of inspections required.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Peru Township or LaSalle County directly.

• Owner-builder exemption — Owner-builder exemption from permit or inspection inside Peru township
• Certificate of occupancy — Certificate of occupancy for new homes inside Peru township
• Local zoning — Land inside Peru township (LaSalle County, IL) outside the City of Peru limits: whether the township itself adopts and administers a zoning ordinance
• Minimum dwelling size — Minimum dwelling size for a single-family home inside Peru township
• Lot coverage — Lot coverage limits for homes inside Peru township

Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.