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

Rules another office applies inside Dimmick Township

Dimmick 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

  Structures on unincorporated land inside Dimmick township that meet the county size thresholds

  • Permit required for structures 200 square feet or larger or with any side 20 feet or greater (brochure).
  • Construction before permit issuance: penalty of double the permit fee.
  • Apply at least 30 days before anticipated building; other county ordinances must be met before issuance.

  structure size threshold: >= 200 sq ft (or any side 20 feet or greater)

  “building permits are required for all commercial projects, all residential structures over 200 square feet or larger than 20 feet on any side”

• Building code adoptedAdopted (with conditions)

  Residential and other structures on unincorporated land inside Dimmick township that require county building permits

  • One- and two-family dwellings: International Residential Code (2024) and 2023/2024 National Electrical Code as amended by the county board.
  • Non-agricultural commercial and multi-family: International Building Code 2024 and related I-codes.
  • Agricultural buildings exempt from county building code inspections (see agricultural exemption claim).

  “residential structures that require building permits are subject to the international residential codes”

• InspectionsRequired

  Structures that receive a county building permit on unincorporated land inside Dimmick township

  • Agricultural buildings declared bona fide agricultural structures are exempt from county building code inspections and fees.
  • Plumbing inspections by Illinois Department of Public Health still apply to agricultural buildings.

  “building code inspections will apply to all structures which receive building permits.”

• Certificate of occupancyRequired

  Occupancy or use of a new structure on unincorporated land inside Dimmick township

  • Occupancy permit is issued by building code inspectors after a final passing inspection.
  • Health department well and septic approval must be certified to the building inspectors before an occupancy permit issues.

  “occupancy and use of a structure (which includes but is not limited to moving furniture and personal items into the structure) is forbidden without an occupancy permit”

• Minimum lot sizeSpecified

  Single-family detached dwellings in the R-2 single family residence district on unincorporated land inside Dimmick township (county zoning)

  • Applies only where the parcel is mapped R-2 on the county zoning district map.
  • Served by public sanitary sewer and water: minimum 10,000 square feet.
  • Served by private sanitary or private water systems: minimum 1 acre.

  minimum lot area, public sewer and water: >= 10000 sq ft (public sanitary sewer and water) · minimum lot area, private sewer or water: >= 1 acre (private sanitary or private water systems)

  “the zoning lot shall be not less than ten thousand (10,000) square feet in size for properties that are served by public sanitary sewer and water and the zoning lot shall not be less than one (1) acre in size for properties served by private sanitary or private water systems”

  2 more reviewed findings on this topic

  • Specified — Single-family detached dwellings in the A-1 agriculture district on unincorporated land inside Dimmick township (county zoning)

    “single family detached dwellings: the zoning lot shall be not less than thirty-five (35) acres”

  • Specified — Single-family detached dwellings in the RR rural residence district on unincorporated land inside Dimmick township (county zoning)

    “single family detached dwellings: the zoning lot shall not be less than one (1) acre in size”

• SetbacksDistrict specific (with conditions)

  Principal buildings in the A-1, AC, RR and R-2 districts on unincorporated land inside Dimmick township; front yard measured from road centerline

  • Front setback 70 ft from township road centerline, 85 ft from county road centerline, 100 ft from state or federal route centerline.
  • Minimum 30 ft from the edge of the road right-of-way or roadway easement in all cases.
  • Side and rear yards 10 ft (A-1 and AC yard tables).

  front yard setback, township road: >= 70 feet (measured from roadway centerline) · front yard setback, county road: >= 85 feet (measured from roadway centerline) · front yard setback, state or federal route: >= 100 feet (measured from roadway centerline)

  “building setbacks in most zoning districts are 70 feet from township road centerline, 85 feet from county road centerline, 100 feet from state/federal route centerline, and 10 feet from side/rear yards”

• Building heightSpecified

  Single-family detached dwellings in the R-2 single family residence district on unincorporated land inside Dimmick township

  • Other structures in R-2 have no height limitation.

  maximum building height, single-family detached dwelling: <= 36 feet

  “maximum height of buildings: all single family detached dwellings shall not exceed thirty-six (36) feet in height”

  One more reviewed finding on this topic

  • Specified — Single-family detached dwellings in the RR rural residence district on unincorporated land inside Dimmick township

    “all other structures shall have no height limitation.”

• Living in an RVLimited

  Living or sleeping in a recreational vehicle on private unincorporated land inside Dimmick township

  • Not allowed for living or sleeping when the RV is located in a subdivision, an unincorporated platted town, or on a parcel with an existing residence, unless otherwise permitted by the ordinance.
  • Recreational vehicle is defined as 400 square feet or less on a single chassis.

  maximum days for living or sleeping in RV: <= 180 days per calendar year (not in subdivision, platted town, or on parcel with existing residence)

  “a recreational vehicle, as defined in chapter 3, may be used for living or sleeping purposes for a period not exceeding 180 days in a calendar year”

• Manufactured homesLimited

  Mobile or manufactured homes used for habitation in the A-1 agriculture district on unincorporated land inside Dimmick township

  • Requires special use approval after public hearing in the A-1 district.
  • Mobile home parks have a separate county ordinance (not opened).

  “trailers/conveyance structures intended for habitation fall under the definition of mobile homes and require special use approval in the a-1 district”

• Septic permitRequired

  New home construction on unincorporated land inside Dimmick township needing septic

  • Approved county health department septic permit must be attached to the building permit application.
  • Septic and well plot plan must show distances to property lines, wells, and sewer lines.

  “copy of approved septic permit from lasalle county health department”

• Septic inspectionRequired

  Occupancy of a new home on unincorporated land inside Dimmick township with a septic system

  • Health department approval certification for the well and septic is required before the building inspectors issue an occupancy permit.
  • Allow at least 48 hours for the health department response.

  “it will take at least 48 hours for a health department response/approval certification for the well and septic of the structure”

• Well permitRequired

  Constructing, modifying, or sealing a water well on unincorporated land inside Dimmick township

  • Permit issued by the LaSalle County Health Department; the well must be inspected and approved before use.
  • Health department may refuse a well permit where public water is reasonably available (see utility connection claim).

  “it shall be unlawful for any person to construct, modify, and/or seal any water well within the county unless he holds a valid permit issued by the health department”

• Mandatory utility hookupConditional

  New single-family home on unincorporated land inside Dimmick township: whether a private well may be permitted where public water is available

  • No mandatory hookup to public water or sewer found in the sections read.
  • Health department may refuse a well permit where a public water supply is reasonably available; a public supply is deemed reasonably available within about 300 feet for a single-family residence.
  • Public sewer is required only for uses in the R-3 district.

  distance to public water supply deemed reasonably available: <= 300 feet (single family residence)

  “a reasonable distance for the purpose of this provision shall be deemed to be not greater than three hundred (300) feet for a single family residence”

• Agricultural exemptionConditional

  Bona fide agricultural buildings on unincorporated land inside Dimmick township

  • Requires documentation of gross agricultural income of $5,000 or more in the prior year and an owner affidavit.
  • Still requires a building permit and zoning certificate; setbacks still apply; a $25.00 agriculture exempt fee is charged.

  agricultural gross income threshold: >= 5000 USD (bona fide agricultural use) · agriculture exempt fee: 25 USD (not a building permit fee)

  “if these structures are declared bona fide agriculture structures and will be used for agricultural purposes they are exempt from county building code inspections and building code fees”

• Subdividing landRegulated (with conditions)

  Dividing a zoning lot on unincorporated land inside Dimmick township into two or more lots

  • Each resulting lot must meet the bulk regulations of its zoning district.
  • Corner lots must be 25 feet wider than the minimum lot width.
  • Land/cash donations required under the LaSalle County subdivision control ordinance.
  • Building permit requires compliance with the county subdivision ordinance; Land Use Department asks to be contacted before subdividing.

  “no zoning lot shall hereafter be divided into two (2) or more lots unless all lots resulting from each such division shall conform with all the applicable bulk regulations of the zoning district where the property is located”

• Driveway accessRequired

  Driveway or road access for a permitted structure on unincorporated land inside Dimmick township

  • Compliance with the LaSalle County highway access ordinance is a prerequisite to building permit issuance; contact the county highway department.
  • Township road access rules are not addressed by the county brochure.

  “lasalle county highway access ordinance for more information contact the lasalle county highway department at 815-434-0743.”

• Building in a floodplainLimited

  Construction on unincorporated land inside Dimmick township that is in a designated floodplain

  • The county floodplain ordinance must be met before a building permit is issued; the floodplain ordinance text was not opened, so its standards are not stated here.
  • Applies only to parcels in 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 mobile home park ordinance setback ordinance zoning ordinance”

• Permit feesPublished (with conditions)

  County building permit fees for residential structures on unincorporated land inside Dimmick township

  • Residential fees are based on square footage and number of inspections; the fee schedule is in Article 6 of the county building permit ordinance (not opened).
  • Fees are nonrefundable and paid when the permit is issued.
  • Agricultural compliance permit fee is $25.00.

  agriculture exempt compliance fee: 25 USD (bona fide agriculture structures)

  “the fee schedule can be found in the lasalle county building permit ordinance “article 6.””

• Permit processPublished (with conditions)

  Building permit application process for unincorporated land inside Dimmick township

  • Application must include building permit form, two sets of construction documents, a site diagram with setbacks, and approved county well and septic permits.
  • Setbacks must be flagged/staked before inspection; inspections scheduled with 48 hours' notice.

  minimum lead time before building: >= 30 days

  “apply for a permit at least 30 days in advance of anticipated building.”

Still unanswered

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

• Owner-builder exemption — Owner-builder exemption for a homeowner building their own home on unincorporated land inside Dimmick township
• Local zoning — Whether Dimmick township itself adopts and administers a zoning ordinance for land inside its limits
• Minimum dwelling size — Minimum dwelling floor area for unincorporated land inside Dimmick township
• Lot coverage — Maximum lot coverage for unincorporated land inside Dimmick township
• Camping on your land — Tent or temporary camping on private unincorporated land inside Dimmick 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.