Bolthole Index

Grundy County, Illinois

Building permits, zoning and land rules in Grundy County, Illinois

41Index Score / 100
#88 of 102 in Illinois

Grundy County, Illinois expressly requires a building permit for renovation of flood-damaged homes in unincorporated areas; we could not confirm whether every other construction project needs one, so ask the county Building Office12. The county's Unified Development Code sets zoning for all development in unincorporated Grundy County3. Septic permits come separately from the Grundy County Health Department, and approval must come before a building permit4.

At a glance

Building permit
Confirmed for renovation of flood-damaged homes in unincorporated Grundy County; ask the Building Office about other work1
Zoning
County zoning and land-use review apply in unincorporated Grundy County3
Septic
County Health Department permit required; installation is inspected, and approval comes before a building permit546
Agricultural buildings
Qualifying farm residences and agricultural structures on farms that are farms in fact are exempt from the county building-code title7
RV living
Travel-trailer housing during permanent-home construction: up to 24 months; permanent RV residence prohibited in county-regulated campgrounds and RV parks89
Building code
Flood-damage renovation plans are reviewed under the 2018 residential code and 2017 electrical code10
Private well
A permit is required before a new well, modification or sealing work begins1112
Owner-builder
No general exemption confirmed; qualifying owner-occupants may do their own plumbing, subject to code, inspection and any local permit131415

Who to call

Building permits

Grundy County Land Use Department, Building Office

Building permits and plan review for unincorporated Grundy County

(815) 941-3120

1320 Union Street, Morris, IL 60450

Online permits →

Zoning

Grundy County Land Use Department, Planning and Zoning Office

Zoning map amendments, subdivision plats, special uses, text amendments and variances for Grundy County; staffs the Zoning Board of Appeals (call (815) 941-3120, the shared Land Use Department line, to reach this office)

Floodplain permits

Grundy County Land Use Department (floodplain / substantial-damage compliance)

Floodplain compliance and substantial-damage review for flood-damaged homes in unincorporated Grundy County (call the Land Use Department at (815) 941-3120)

Septic permits

Grundy County Health Department, Environmental Health Division

Private sewage disposal (septic) permits, private well permits, and well/septic property-transfer inspections for Grundy County

(815) 941-3115

environmentalhealth@grundycountyil.gov

1320 Union St. Morris, IL 60450

Roads & driveways

Grundy County Highway Department

Construction and maintenance of county highways and bridges; posts an Access Permit Application for driveways onto county roads (township roads are handled by the township road commissioner instead)

(815) 942-0363

245 N. Illinois Route 47, Morris, IL 60450

Online permits →

Contact details are copied from each office’s official page and were checked against it on October 12, 2026.

Off-grid gear

Going off-grid in Grundy County means bringing your own water and power. The kit we’d start with:

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Do you need a building permit in Grundy County, Illinois?

Grundy County expressly requires a building permit when a flood-damaged home in unincorporated Grundy County needs renovation work1. The available county rule does not establish that every other type of construction requires a permit, so ask the Building Office about the exact project before ordering plans or materials2. For those flood-damage renovations, the county reviews plans for compliance with the 2018 International Residential Code and 2017 National Electric Code10. Qualifying farm residences and agricultural buildings or structures are exempt from the county building-code title only when they sit on a farm that is a farm in fact and their use fits the statutory agricultural definition7. We could not confirm a general owner-builder exemption from local building permits, inspections or codes13.

Inside municipal limits, Morris16, Mazon17 issue their own building permits. Braidwood18, Godley19 also issue their own building permits and extend into Grundy County from Will County. Where a private septic system is allowed on land in Grundy County, septic approval stays with the Grundy County Health Department54.

Who is the Grundy County Building Office, and how do you reach them?

The Grundy County Land Use Department's Building Office handles building permits and plan review for unincorporated Grundy County2. The office is at 1320 Union Street, Morris, IL 60450, and the shared Land Use Department number is (815) 941-31202. Office hours are Monday through Friday, 8 a.m. to 4:30 p.m.2. For flood-damage renovation permits, the county completes a full plan review and checks that the contractor is properly licensed with Grundy County before issuing the permit20. The county publishes a 2026 fee-resolution link, but the available record does not establish the amount for a particular project21. Ask the Building Office for the current fee, required plans, inspections and closeout documents; we could not confirm a general inspection schedule or certificate-of-occupancy requirement2223.

Does Grundy County have zoning?

The county Unified Development Code applies to all development in unincorporated Grundy County3. The Agricultural, Agricultural Residential, Planned Residential, Residential, Commercial General, Commercial Interchange and Industrial districts have an official map maintained at the County Administrative Building24. Minimum lot size, setbacks and building height vary by district; ask Planning and Zoning for the parcel’s district and dimensional standards25262728. The UDO includes concept-plan, minor- and major-subdivision, certificate and recording procedures; the planning office also evaluates preliminary and final plats against the Comprehensive Plan and Stormwater Ordinance2930.

Morris31, Minooka32, Coal City33, Diamond34, Gardner35 set their own municipal zoning. Braidwood36, Dwight37, Seneca38, Godley39 also set their own zoning and reach into Grundy County from neighboring counties. Municipal zoning does not replace Grundy County Health Department approval for private septic systems on land in Grundy County54.

How do septic permits work in Grundy County?

The Grundy County Health Department's Environmental Health Division administers private sewage disposal systems countywide5. A permit is required for a compliant new system and for repairs, and the county says to allow up to 72 hours for review4. An approved water and sewage system permit must be in hand before the county will issue a building permit4. The Health Department inspects installation work on every private sewage disposal system to confirm correct installation, but the reviewed rule does not establish a universal recurring-inspection interval6. USDA rates 0% of Grundy County soils as free of severe limits for a conventional drain field, so do not assume a simple conventional layout will fit without site-specific review40.

Can you live in an RV or tiny home on your land in Grundy County?

In unincorporated Grundy County, camping and travel trailers, excluding mobile homes, may provide temporary housing during construction of a permanent home for no more than 24 months, subject to the UDO’s residential-parcel trailer provisions8. County-regulated campgrounds and RV parks may operate as a special use in the Agricultural district, but prohibit permanent residence in an RV or tent9. We could not confirm a tiny-home occupancy or minimum dwelling-size rule; ask Planning and Zoning before choosing a dwelling28. Illinois allows compost toilets and other approved human-waste systems subject to construction and maintenance rules, but other household wastewater still requires a conventional private sewage disposal system41.

What are the steps to build a home in Grundy County, in order?

  1. Confirm that the parcel is unincorporated, then ask Planning and Zoning to identify its zoning district, allowed use, setbacks and any subdivision review32429.
  2. Ask the Building Office whether the proposed work requires a building permit, which application applies and what the current fee is; the county publishes a fee-resolution link2021.
  3. Apply to the Health Department for septic approval and any required well permit; septic review may take up to 72 hours411.
  4. If the work is a flood-damage renovation, submit plans for county review under the 2018 International Residential Code and 2017 National Electric Code10.
  5. Arrange the required septic installation inspection with the Health Department6.
  6. For state-road access, obtain an IDOT permit before work; for a county road, ask the Highway Department what approval applies4243.

What should you check before you buy land in Grundy County?

Before closing, confirm whether the parcel is in unincorporated Grundy County and have Planning and Zoning identify its mapped district, allowed use, setbacks and any subdivision constraints32430. Check septic feasibility early because 0% of county soils are rated free of severe limits for a conventional drain field40. A new, modified or abandoned well requires a permit before work begins, and Grundy County says well applications may take up to 72 hours to process1112. Check flood exposure before choosing a homesite: when flood damage reaches 50% or more of pre-flood market value, repairs cannot begin until the structure complies with the floodplain ordinance, potentially through elevation or flood-proofing44. Property taxes average about 2%, with a median annual bill near $5,2604546.

Watch-outs

  • For flood-damaged structures in unincorporated Grundy County, the 50% substantial-damage threshold is measured against pre-flood market value, and repair costs include materials and labor even when the homeowner does the work; floodplain compliance must precede repairs when the threshold is met44.
  • Illinois lets a qualifying owner-occupant perform plumbing on a single-family home, but the work must meet the state plumbing code, remains subject to inspection and may still need a local plumbing permit; this is not a general owner-builder exemption1415.
  • A travel trailer can be lived in on a residential parcel in unincorporated Grundy County only during construction of a permanent home and for no more than 24 months; we could not confirm a tiny-home rule, so call the Planning and Zoning Office first828.

Sources

  1. grundycountyil.gov, quoted and re-checked
  2. Grundy County Land Use Department, Building Office (grundycountyil.gov)
  3. codelibrary.amlegal.com, quoted and re-checked
  4. Environmental Health, quoted and re-checked
  5. Environmental Health, quoted and re-checked
  6. Environmental Health, quoted and re-checked
  7. 6-1-4: Agricultural Exemptions, quoted and re-checked
  8. 8-2-3-12: Residential Storage of Trailers and Boats, quoted and re-checked
  9. 8-2-5-3: Campgrounds and Recreational Vehicle Parks, quoted and re-checked
  10. grundycountyil.gov, quoted and re-checked
  11. 77 Ill. Admin. Code 920.130, Water Well Permit Requirements (Illinois statewide rule), quoted and re-checked
  12. Environmental Health, quoted and re-checked
  13. Illinois Codes FAQ (Illinois statewide rule), quoted and re-checked
  14. HB5913 Enrolled — Illinois Plumbing License Law amendment (Illinois statewide rule), quoted and re-checked
  15. 225 ILCS 320/18 — Local regulation; Department standards (Illinois statewide rule), quoted and re-checked
  16. Morris: Building & Zoning | City of Morris (Grundy County), quoted and re-checked
  17. Village of Mazon: § 151.050 BUILDING PERMITS. (Grundy County), quoted and re-checked
  18. Braidwood: Code of Ordinances City of Braidwood, Illinois (Grundy County), quoted and re-checked
  19. Village of Godley: § 154.088 Permit requirements (Grundy County), quoted and re-checked
  20. grundycountyil.gov, quoted and re-checked
  21. Land Use, quoted and re-checked
  22. Illinois Codes FAQ (Illinois statewide rule), quoted and re-checked
  23. Illinois Codes FAQ (Illinois statewide rule), quoted and re-checked
  24. Chapter 1 Jurisdiction and Zoning Districts, quoted and re-checked
  25. Chapter 3 District Intensity and Bulk Standards, quoted and re-checked
  26. Chapter 3 District Intensity and Bulk Standards, quoted and re-checked
  27. Chapter 3 District Intensity and Bulk Standards, quoted and re-checked
  28. Grundy County Land Use Department, Planning and Zoning Office (grundycountyil.gov)
  29. Chapter 14 Permits and Procedures, quoted and re-checked
  30. Planning Office, quoted and re-checked
  31. Morris: Morris Code Sec. 48-324, Establishment (Grundy County), quoted and re-checked
  32. Village of Minooka: Planning and Zoning (Grundy County), quoted and re-checked
  33. Village of Coal City: Village of Coal City, Illinois Code of Ordinances — Table of Contents (Grundy County), quoted and re-checked
  34. Village of Diamond: § 151.056 Districts (Grundy County), quoted and re-checked
  35. Village of Gardner: official source (Grundy County), quoted and re-checked
  36. Braidwood: Code of Ordinances City of Braidwood, Illinois (Grundy County), quoted and re-checked
  37. Village of Dwight: Table of Contents - Village of Dwight, IL (Grundy County), quoted and re-checked
  38. Village of Seneca: Seneca, Illinois Code of Ordinances (Grundy County), quoted and re-checked
  39. Village of Godley: official source (Grundy County), quoted and re-checked
  40. Share of soils USDA rates "not limited" for a conventional septic drain field (SSURGO). A strict rating: the median county is about 6% and a tenth of counties are 0%, so a low figure means most lots need a site evaluation or an engineered system, not that septic is impossible. Cite it only with that caveat: Bolthole Index county data
  41. 77 Ill. Adm. Code 905.130 Human Waste Disposal (Illinois statewide rule), quoted and re-checked
  42. Highway Permits (Illinois statewide rule), quoted and re-checked
  43. Grundy County Highway Department (grundycountyil.gov)
  44. grundycountyil.gov, quoted and re-checked
  45. Effective property tax rate: Bolthole Index county data
  46. Median property tax bill: Bolthole Index county data

Written October 12, 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.

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Compared with neighboring counties

Like all 6 of its neighbors, Grundy County has countywide zoning.

RuleGrundy CountyKendall CountyLaSalle CountyWill CountyKankakee CountyLivingston CountyDeKalb County
Building permitRequiredRequiredRequiredRequiredRequiredLimitedRequired
County zoningYesYesYesYesYesYesYes
Septic permitsCounty Health Dept.County Health Dept.County Health Dept.County Health Dept.County Health Dept.County Health Dept.County Health Dept.

County locator

Grundy County in Illinois

41
County map
Grundy County highlighted among the Illinois counties · colored by Index score

How Grundy County scores

Seclusion19100% ev.
Self-Sufficiency52100% ev.
Admin Boringness4390% ev.
Durability55100% ev.
Property Autonomy42100% ev.
Carry Cost49100% ev.

Evidence strength: 98%. This reports direct-source completeness and fallback use; it is separate from the score and is not a confidence interval. How it works →

$323kTypical home
2%Property tax
$10,311Land / acre
37.7"Annual rain
1.4% of yrsSevere drought
5.6 / yr (+5.3)Mid-century 100°F days
14.5 daysMid-century dry spell
1.77" (+5.6%)Mid-century 1-day rain
1.75×Wildfire change factor
100%Forward climate coverage
$1,672Home insurance / yr
4.4% / yrInsurance growth
0.66%Nonrenewal rate
county median (2+ published ZIPs)Insurance basis
66,022People within 30 min
11,123,541People within 2 hr
62,470Radius comparison (15 mi)
128.1People / sq mi
0%Federal land
97.4%Land at 15% slope or less
0%Soils rated "not limited" for septic (strict USDA rating)
0 acWorkable land screen
14.9%Wooded land
62.3 tonsBiomass / forest ac
50.7°FAvg temp

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Cities and towns in Grundy County

Inside a city or town, that city usually issues building permits and sets zoning; the county’s rules above cover unincorporated land. Septic, wells and floodplain rules usually stay with the county or state everywhere.

Not yet researched: Aux Sable Township · Braceville Township · Village of Channahon · Village of East Brooklyn · Erienna Township · Felix Township · Garfield Township · Goodfarm Township · Goose Lake Township · Greenfield Township · Highland Township · Village of Kinsman · Maine Township · Mazon Township · Morris Township · Nettle Creek Township · Norman Township · Saratoga Township · Village of South Wilmington · Village of Verona · Vienna Township · Wauponsee Township

Answers from the rulebook for Grundy County

What the ordinances and state agencies actually say — one answer per question, each quoted from the official source and independently re-checked.

Grundy County rules

  • Building permitRequired

    Renovation work on flood-damaged homes in unincorporated Grundy County.

    • The page limits the statement to residents in unincorporated Grundy County whose homes had damage in the flooding conditions described on the page.
    • Before issuance, the county checks contractor licensing.
    • Repairs costing 50 percent or more of pre-flood market value trigger floodplain-ordinance compliance before repairs begin.

    substantial-damage threshold: >= 50 percent of structure pre-flood market value (Special floodplain conditions apply.)

    “Residents who are living in unincorporated Grundy County (not in a city or village) that have had damage in the last flooding conditions are required to get a building permit for the renovation work that may be necessary.”
    One more reviewed finding on this topic
    • Required — Renovation work for flood-damaged homes in unincorporated Grundy County, not in a city or village.
      “Residents who are living in unincorporated Grundy County (not in a city or village) that have had damage in the last flooding conditions are required to get a building permit for the renovation work that may be necessary.”
  • Building code adoptedAdopted (with conditions)

    Construction proposed for flood-damaged homes in unincorporated Grundy County.

    • The source describes application to renovation work for homes damaged in flooding conditions.
    • A full plan review is completed before the permit is issued.
    • The contractor must be properly licensed with Grundy County before a permit is issued.

    residential building code: 2018 International Residential Code · electrical code: 2017 National Electric Code

    “Our office completes a full plan review that ensures that the construction proposed complies with the 2018 International Residential Code and the 2017 National Electric Code.”
    One more reviewed finding on this topic
    • Partial — Flood-damage renovation work in unincorporated Grundy County.
      “Our office completes a full plan review that ensures that the construction proposed complies with the 2018 International Residential Code and the 2017 National Electric Code.”
  • County-wide zoningPresent (with conditions)

    Development in unincorporated Grundy County.

    • Municipal annexation can modify the unincorporated area subject to the UDO.
    • The official code states that all development within unincorporated Grundy County must comply with the UDO.
    “All development within the boundaries of unincorporated Grundy County, as may be modified from time to time by municipal annexation, and all land use applications made to the county for property within the county shall comply with the provisions of this UDO.”
  • Zoning districtsPublished (with conditions)

    Zoning districts established by the Grundy County Unified Development Code.

    • The official zoning map is held in the Office of the Grundy County Land Use Department and maintained in the County Administrative Building.
    • The code identifies the 2023 Code as current on the code-library page.
    • District-specific standards and use permissions apply.
    “A. General: The following zoning districts are established: [...] A - Agricultural. AR - Agricultural residential. [...] PR - Planned residential. R - Residential. [...] CG - Commercial general. CI - Commercial interchange. I - Industrial.”
    One more reviewed finding on this topic
    • Published (with conditions) — Zoning districts and the official zoning map for unincorporated Grundy County.
      “The official zoning map is on file in the County Administrative Building; it is maintained to reflect all zoning district boundary amendments.”
  • Minimum lot sizeDistrict specific (with conditions)

    Development parcels governed by the Unified Development Code.

    • Requirements vary by zoning district and applicable land use.
    “The purpose of this chapter is to establish the general standards for the character of development that is allowed within each zoning district. [...] Minimum lot area requirements for all land uses.”
  • SetbacksDistrict specific (with conditions)

    Individual lots governed by the Unified Development Code.

    • Requirements vary by zoning district and applicable land use.
    “The character of development of individual lots is regulated by minimum requirements for building height, lot dimensions, setbacks, floor area ratios, and open space or impervious surface limitations.”
  • Building heightDistrict specific (with conditions)

    Individual lots governed by the Unified Development Code.

    • Requirements vary by zoning district and applicable land use.
    “The character of development of individual lots is regulated by minimum requirements for building height, lot dimensions, setbacks, floor area ratios, and open space or impervious surface limitations.”
  • Living in an RVTemporary only (with conditions)

    Temporary residential use of a camping trailer, travel trailer, or other trailer, excluding mobile homes, on a residential parcel during construction of a permanent residential unit.

    • The trailer must be on a lot containing a single-family detached dwelling or otherwise qualify under the listed trailer provisions.
    • Temporary residential use is limited to construction of a permanent residential unit.
    • The temporary residential use may not exceed twenty-four (24) months.
    • The UDO applies to development within unincorporated Grundy County.

    maximum temporary residential use period: <= 24 months (during construction of a permanent residential unit)

    “The following provisions shall apply to the temporary storage of trailers and boats on residential parcels: A. Trailers: Camping trailers, travel trailers, and other trailers (not including mobile homes) shall only be permitted: [...] 4. Temporary residential use during construction of a permanent residential unit for a period not to exceed twenty four (24) months.”
    One more reviewed finding on this topic
    • Prohibited — Permanent residence in a recreational vehicle or tent at a county-regulated campground or recreational vehicle park in unincorporated Grundy County.
      “Campgrounds and RV parks may be allowed as a special use in the agricultural (A) district, subject to the following provisions: A. Residential Use Prohibited: No recreational vehicle or tent shall be used as a permanent place of residence.”
  • Who permits septicCounty (with conditions)

    Private sewage disposal systems in Grundy County.

    • The Grundy County Health Department Environmental Health Division performs the county private sewage disposal system functions.
    • The program also links to the Illinois Department of Public Health private sewage disposal code.
    “The Environmental Health Division performs the following functions within the Private Disposal System Program (aka Septic Systems):”
    One more reviewed finding on this topic
    • County — Private sewage disposal systems administered through the Grundy County Environmental Health Division.
      “The Environmental Health Division performs the following functions within the Private Disposal System Program (aka Septic Systems):”
  • Septic permitRequired

    Private sewage disposal systems and building permits in Grundy County.

    • An approved water and sewage system permit is required to obtain a building permit.
    • Private sewage disposal permits may take up to 72 hours to process and review.
    • Permits are required for repairs to existing septic systems.

    processing time: <= 72 hours (The page says to allow up to 72 hours for processing and reviewing all private sewage disposal system permits.)

    “In order to obtain a building permit, you must have an approved water & sewage system permit. Allow up to 72 hours for the processing and reviewing of all private sewage disposal system permits.”
  • Septic inspectionRequired

    Installation work for all private sewage disposal systems.

    • The county inspection concerns installation work and verifies correct installation.
    • Periodic tank pumping and inspection is described as essential, but the page does not state a universal periodic inspection mandate.
    “Inspects the installation work performed on all private sewage disposal systems to ensure that the system is installed correctly.”
    One more reviewed finding on this topic
    • Required — Installation of private sewage disposal systems in Grundy County.
      “Inspects the installation work performed on all private sewage disposal systems to ensure that the system is installed correctly.”
  • Well permitLimited

    Private water wells, especially abandoned or soon-to-be-abandoned wells, in Grundy County.

    • The Environmental Health Division reviews well permit applications and processes permits.
    • For wells that are abandoned or to be abandoned, a permit and fee are required and the county health department must be on-site to witness sealing.
    • The page states that private water-well permit applications may take up to 72 hours to review and process.

    processing time: <= 72 hours (The page says it may take up to 72 hours to review and process private water well permit applications.)

    “Wells that are abandoned or to be abandoned must be sealed by a licensed contractor or homeowner. A permit and fee is required and GCHD must be on-site to witness the procedure.”
  • Agricultural exemptionAvailable (with conditions)

    Farm residences and other buildings or structures used for agricultural purposes on qualifying farms.

    • The exemption is provided by State Statute.
    • The residence, building, or structure must be located on a farm that is such in fact and not in name only.
    • The use must be limited to uses defined as agricultural in 55 Illinois Compiled Statutes 5/5-12001.
    “Exempt from the provisions of this title, as provided by State Statute, are farm residences and other buildings and structures used for agricultural purposes on farms. To be considered exempt, such residence, building or structure shall be located on a farm that is such in fact and not in name only; and the use shall be limited to those uses defined as agricultural in 55 Illinois Compiled Statutes 5/5-12001.”
  • Subdividing landRegulated (with conditions)

    Preliminary and final plats and related subdivision review in Grundy County.

    • The planning office evaluates plats for compliance with the current Comprehensive Plan and Stormwater Ordinance.
    • The cited source describes evaluation and recommendation, not every approval step or exemption.
    “The Planning Office evaluates concept plans, preliminary and final plats, map amendments for compliance with the current Comprehensive Plan, compliance with the Stormwater Ordinance, conditional uses, text amendments and comprehensive planning for the land uses, transportation of Grundy County.”
    One more reviewed finding on this topic
    • Regulated (with conditions) — Subdivision and division of land subject to the Unified Development Code.
      “8-14-10: Subdivision Plat Procedures 8-14-10-1: Concept Plan 8-14-10-2: Minor Subdivisions 8-14-10-3: Major Subdivisions 8-14-10-4: Required Certificates 8-14-10-5: Recording”
  • Building in a floodplainLimited

    Flood-damaged structures in unincorporated Grundy County, including structures within floodplain regions.

    • Special conditions may apply when total repair costs are 50 percent or more of the structure’s pre-flood market value.
    • If damage is 50 percent or more, repairs must not begin until the structure complies with the floodplain ordinance.
    • Compliance may require elevating or flood-proofing the structure.
    • Repair costs are calculated by assuming full repair to the pre-damaged condition and include structural materials, finish materials, and labor, even if the homeowner performs the work.
    • Repetitive damage is also considered for homes within floodplain regions.

    repair-cost threshold: >= 50 percent of pre-flood market value

    “Special conditions may be applied to buildings that have a total cost of repairs that is 50 percent or more of the structure’s pre-flood market value. If a building is found to be damaged 50 percent or more, regulations require that repairs do not begin until that structure complies with the floodplain ordinance. This may require elevating or flood-proofing the structure to prevent future damage to the structure in future flooding conditions.”
    One more reviewed finding on this topic
    • Required — Flood-damaged structures in unincorporated Grundy County.
      “If a building is found to be damaged 50 percent or more, regulations require that repairs do not begin until that structure complies with the floodplain ordinance. This may require elevating or flood-proofing the structure to prevent future damage to the structure in future flooding conditions.”
  • Permit feesPublished

    County land-use and building-permit fee information for unincorporated Grundy County.

    • The official Land Use page provides a linked document titled “2026 Fee Resolution.pdf.”
    • The accessible webpage does not expose the fee amounts from that linked PDF.

    fee schedule: 2026 Fee Resolution.pdf

    “2026 Fee Resolution.pdf document seq 0.00”
  • Permit processPublished (with conditions)

    Permit processing for flood-damage renovation work in unincorporated Grundy County.

    • The County office completes a full plan review.
    • The review checks compliance with the 2018 International Residential Code and the 2017 National Electric Code.
    • The contractor must be properly licensed with Grundy County before a permit is issued.
    “Our office completes a full plan review that ensures that the construction proposed complies with the 2018 International Residential Code and the 2017 National Electric Code. Also, before a permit is issued, our assistant does make sure that the contractor is properly licensed with Grundy County.”
    One more reviewed finding on this topic
    • Published (with conditions) — County zoning and subdivision permit procedures under Title 8.
      “CHAPTER 14 PERMITS AND PROCEDURES [...] 8-14-2: General Procedures [...] 8-14-2-1: Preapplication Conference [...] 8-14-2-2: Applications [...] 8-14-2-3: Application Completeness Review [...] 8-14-2-4: Application Review”

Illinois rules that apply here

  • Owner-builder exemptionConditional

    Owner occupants or lessee occupants of single-family residences, and owners of single-family residences under construction for their own occupancy, performing plumbing planning, installation, alteration, or repair in Illinois.

    • The exemption is limited to plumbing work on the specified single-family residence; the cited statute does not establish a general owner-builder exemption for all construction trades or a statewide exemption from building permits.
    • The plumbing must comply with the minimum standards in the Illinois State Plumbing Code.
    • The plumbing is subject to inspection by the Illinois Department of Public Health or by the local governmental unit if it retains a licensed plumber as inspector.
    • The owner, owner occupant, or lessee occupant may not employ anyone other than a plumber licensed under the Illinois Plumbing License Law to assist.
    • An occupant must have taken possession of and be living in the premises as their bona fide sole and exclusive residence, or, for a residence under construction, expect to take possession and live there as that residence, with current intent to live there for at least 6 months after completion of the plumbing work or, for a residence under construction, at least 6 months after completion of construction.
    • Failure to possess and live in the premises as a sole and exclusive residence for 6 months or more creates a rebuttable presumption that the required intent was lacking.

    minimum occupancy period: >= 6 months (After completion of plumbing work; for a residence under construction, after completion of construction.)

    “Nothing herein contained shall prohibit the owner occupant or lessee occupant of a single family residence, or the owner of a single family residence under construction for his or her occupancy, from planning, installing, altering or repairing the plumbing system of such residence”
    2 more reviewed findings on this topic
    • Conditional — Privately funded construction in Illinois, including projects performed by an owner-builder, as to state-issued building permits, state plan review, state building-code inspections, and state occupancy permits.
      “No. If any of these are required, they would be addressed by the unit of local government.”
    • Conditional — Statewide treatment of local plumbing permits and inspections for qualifying owner occupants performing plumbing work on a single-family residence.
      “Nothing contained in this Act shall prohibit any city, town, village, township or county from providing for a Plumbing Inspector or from requiring permits for the installation and repair of plumbing and collecting a fee therefor, but a city, town, village, township, or county that requires a permit for installation and repair of plumbing may not issue that permit without verification that the applicant has a valid plumbing license or that the applicant is the owner occupant of a single family residence that is the subject of the permit.”
  • InspectionsLimited

    Privately funded construction statewide in Illinois, as to inspections performed by the State rather than by a local authority having jurisdiction.

    • The Illinois Capital Development Board does not perform building-code inspections for privately funded construction.
    • If inspections are required, they are addressed by the applicable unit of local government.
    • A local municipality or county may be a non-building-code jurisdiction, in which case applicable state baseline requirements and inspection-certification provisions may apply.
    “No. If any of these are required, they would be addressed by the unit of local government.”
    One more reviewed finding on this topic
    • Not required — Building-code-compliance inspections performed by the State of Illinois for privately funded construction.
      “No. If any of these are required, they would be addressed by the unit of local government.”
  • Certificate of occupancyLimited

    Occupancy permits or certificates for privately funded construction in Illinois.

    • The State does not issue occupancy permits for privately funded construction.
    • If an occupancy permit is required, it is addressed by the applicable unit of local government.
    “No. If any of these are required, they would be addressed by the unit of local government.”
    One more reviewed finding on this topic
    • Not required — Issuance of occupancy permits or certificates by the State of Illinois for privately funded construction.
      “No. If any of these are required, they would be addressed by the unit of local government.”
  • Manufactured homesAllowed (with conditions)

    Occupancy of manufactured homes as dwellings, including occupancy in manufactured home communities regulated by IDPH.

    • Manufactured home communities with 5 or more sites must be licensed by IDPH, except communities located in home rule units.
    • IDPH annually inspects licensed communities for renewal, including water, sewage disposal, electrical systems, lighting, roads, spacing of homes, and garbage disposal.
    • Manufactured homes moved since January 1, 1980 must be secured using equipment meeting IDPH standards.
    • Effective December 31, 2001, manufactured homes must be installed by an Illinois licensed manufactured home installer or the homeowner and installed according to manufacturer instructions; if unavailable, the IDPH Manufactured Home Installation Code applies.
    • Local zoning, building, floodplain, and utility requirements may also apply.

    manufactured home community license threshold: >= 5 sites (Communities located in home rule units are excepted from this IDPH licensing statement.) · moved-home tiedown requirement effective date: >= 1980-01-01 · installation requirement effective date: >= 2001-12-31

    “designed and situated so as to permit its occupancy as a dwelling place for one or more persons”
  • Off-grid sanitationAllowed (with conditions)

    Off-grid disposal of human wastes through privies, portable toilets, recirculation toilets, incinerator toilets, and compost toilets statewide in Illinois.

    • Other domestic wastes must be disposed of in a conventional private sewage disposal system.
    • Compost toilets may also be used for other organic domestic wastes.
    • Privies have construction, capacity, venting, maintenance, and abandonment requirements.
    • A privy pit must have a minimum capacity of 50 cubic feet per seat.
    • A privy must be pumped when filled to within 18 inches of the bottom of the riser.
    • Vault privies are required where groundwater or limestone formations are within 4 feet of the bottom of the pit.
    • Recirculating toilets must meet NSF International/ANSI Standard 41 and residuals must go to an approved public or private sewage disposal system.
    • Incinerator and compost toilets have separate maintenance and disposal requirements; compost toilets must meet NSF International/ANSI Standard 41.

    privy pit minimum capacity: >= 50 cubic feet per seat · privy pumping trigger: <= 18 inches from bottom of riser (Pump when filled to within this distance.) · vault-privy groundwater or limestone separation: < 4 feet from bottom of pit (Watertight, non-metal vaults are required where the condition applies.)

    “Privies, portable toilets, recirculation toilets, incinerator toilets and compost toilets are approved for private sewage disposal of human wastes.”
  • Driveway accessRequired

    Work within the right-of-way of an Interstate, U.S. state route, Illinois state route, or state-maintained roadway, including access-driveway requests to State highways.

    • A permit must be obtained before work begins.
    • Requirements may vary by IDOT district; the applicant must contact the district office for specific requirements.
    • IDOT's access-driveway handbook guides what is allowable for highway access requests.
    “Per 605 ILCS 5/4 209, IDOT requires a permit when working within the right-of-way of an Interstate, U.S. state route, Illinois state route, or state maintained roadway. A permit must be obtained prior to the start of any work and a copy of the approved permit must be at the worksite at all times.”
  • Short-term rentalsLimited

    Short-term rentals in Illinois where at least one room is rented for fewer than 30 consecutive days and accommodations are reserved in advance, when the hosting platform meets the statutory definition of a re-renter.

    • Beginning July 1, 2025, qualifying hosting platforms are subject to Hotel Operators’ Occupation Tax.
    • The source establishes tax and registration obligations, not statewide land-use permission; local zoning and licensing may separately apply.

    rental period: < 30 consecutive days

    “Beginning July 1, 2025, hosting platforms for short-term rentals that meet the definition of “re-renter” are subject to Hotel Operators’ Occupation Tax.”
  • Campground & park staysAllowed (with conditions)

    Overnight camping in Illinois campgrounds subject to the Campground Licensing and Recreational Area Act.

    • IDPH annually inspects and licenses campgrounds in Illinois.
    • The state campground definition includes camping and temporary parking of recreational vehicles.
    • Campgrounds within home rule units of government are exempt from the state campground licensing requirement.
    • Recreational areas without overnight camping, such as highway rest stops and picnicking areas, are subject to the rules but are not licensed or routinely inspected.

    minimum persons for statutory campground threshold: >= 10 persons · minimum camping duration for statutory campground threshold: >= 6 camping days per calendar year

    ““Camping Day” means any 24 hour period or portion thereof during which the participants remain overnight at the site.”
  • county building authorityLimited

    County building-construction and building-code regulation, including residential structures, in counties meeting the statutory population and metropolitan-area conditions.

    • The county must have a population not in excess of 1,000,000.
    • The county must be located in the area served by the Northeastern Illinois Metropolitan Area Planning Commission.
    • Rules are subject to rules or regulations adopted by the State Fire Marshal under the cited gasoline and volatile-oils statute.
    • The county must exempt municipalities located wholly or partly within the county when the municipal building code is equal to the county regulation and local authorities are enforcing that municipal code.
    • The rules apply throughout the county, but municipalities may establish higher standards.
    • The rules do not apply to construction or alteration of buildings or structures used or to be used for agricultural purposes on a tract zoned and used for agricultural purposes.
    • The county board must follow the publication and posting requirements in 55 ILCS 5/5-1063.
    • Beginning on the effective date of the amendatory Act of the 92nd General Assembly, a county adopting a new building code or amending an existing building code must provide the building-code identification to the Capital Development Board under Section 10.18 at least 30 days before adoption.
    • Violations are petty offenses, and enforcement is by an officer designated by county-board resolution.
    • The provision expressly authorizes county building-construction and building-code rules, but the opened text does not expressly use the phrase residential building permit requirement.

    population threshold: <= 1000000 persons (The county must be located in the area served by the Northeastern Illinois Metropolitan Area Planning Commission.) · pre-adoption identification period: >= 30 days (Applies to a new building code or amendment under the stated amendatory-Act provision.)

    “The county board in any county with a population not in excess of 1,000,000 located in the area served by the Northeastern Illinois Metropolitan Area Planning Commission may prescribe by resolution or ordinance reasonable rules and regulations (a) governing the construction and alteration of all buildings and structures and parts and appurtenances thereof and governing the maintenance thereof in a condition reasonably safe from the hazards of fire, explosion, collapse, contagion and the spread of infectious disease”
    One more reviewed finding on this topic
    • General — Illinois counties adopting and enforcing building codes and issuing building permits for residential construction in unincorporated areas, subject to the statewide baseline framework.
      “A municipality or county is not required to adopt building codes. If they do NOT adopt a building code then they are considered a non-building code jurisdiction and section 10.09-1 of the Capital Development Board Act (20 ILCS 3105) applies. If they do adopt a building code(s) then it must comply with section 10.18 of the Capital Development Board Act (20 ILCS 3105).”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission — ask the county directly.

  • Local zoning — Aggregate local zoning across municipalities and unincorporated areas of Grundy County.
  • Minimum dwelling size — Minimum dwelling size in unincorporated Grundy County.
  • Lot coverage — Lot coverage in unincorporated Grundy County.
  • Camping on your land — Temporary camping on private land in unincorporated Grundy County.
  • Tiny homes — Tiny-home occupancy in unincorporated Grundy County.
2 more unanswered
  • Accessory dwellings
  • Mandatory utility hookup

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.

Living off-grid in Grundy County, Illinois

Is Grundy County a good place to live off-grid or homestead?

Grundy County scores 41/100 on the Bolthole Index, a marginal county profile. Watch-outs: about 66,022 people within a 30-minute drive.

Do you need a building permit in Grundy County, Illinois?

Grundy County generally requires a residential building permit, and it enforces county zoning. Onsite septic is permitted by Grundy County Health Department, Environmental Health Division. Owner-builders may act as their own contractor to build their home. These answers are quoted from official sources and independently re-checked. Rules change and cities within the county differ — always confirm with the county before you buy or build.

Can you live in an RV or tiny home on your land in Grundy County?

Living in an RV on your own land in Grundy County is allowed on a temporary basis only: Temporary residential use of a camping trailer, travel trailer, or other trailer, excluding mobile homes, on a residential parcel during construction of a permanent residential unit. The trailer must be on a lot containing a single-family detached dwelling or otherwise qualify under the listed trailer provisions. Temporary residential use is limited to construction of a permanent residential unit. Confirm with the county before relying on it.

How much does land cost in Grundy County, Illinois?

Land in Grundy County runs about $10,311 per acre, based on the latest county data.

What is the water situation in Grundy County?

Grundy County gets about 37.7" of rain a year, with severe drought in roughly 1.4% of years.

How remote is Grundy County?

A representative private-land location has about 66,022 people within a 30-minute drive and 11,123,541 within two hours. The road-network catchments count population across county lines and clusters of smaller cities; straight-line radius values remain available as a comparison.

How Grundy compares in Illinois

Compare side-by-side →See all 102 Illinois counties ranked →