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

Yes. DeKalb County reviews and issues building permits for covered construction in unincorporated areas; starting permit-required work early doubles the permit fees⁴. Unincorporated DeKalb County uses the 2021 International Building Code with county amendments, alongside adopted electrical and state plumbing requirements⁴. The permit holder or agent must give the building official at least 1 work day's notice when work is ready for inspection⁴. A building governed by Chapter 14 cannot be used or occupied until the building official issues a certificate of occupancy or completion⁴. Agricultural exemption does not mean no county paperwork: an exempt farm structure must obtain an Agricultural Exempt Structure Construction Card and still comply with county setback and stormwater requirements⁴.

DeKalb County Community Development issues building permits for unincorporated land; call 815-895-7188 or email dhiland@dekalbcounty.org, or visit the Administration Building, 110 E. Sycamore Street, Sycamore, IL 60178¹. Submit applications, attachments and payment in hard copy; electronic submissions are not accepted⁷. A new one- or two-family residence costs $0.60 per square foot of floor area, plus separate $150 electrical, $150 plumbing and $150 mechanical fees⁸. An owner-occupant acting as a subcontractor may submit a Homeowner Exemption Contractor Registration Form; the form does not waive all contractor or code requirements⁶.

Sycamore⁹, Sandwich¹⁰, Hinckley¹¹, Shabbona¹² handle their own building permits. Septic permits remain a separate Health Department matter³.

DeKalb County zoning applies to unincorporated land, outside incorporated municipalities². Minimum lot area varies: 40 acres for an A1 farm residence, 1 acre in RC-1 unless a drain field needs more land, and 22,000 square feet for an RC-2 single-family dwelling². Setbacks, height and lot coverage also depend on district; ask Community Development to confirm the parcel's standards and allowed use^1,2. Subdivision approval goes to the Planning, Zoning and Development Committee and County Board¹.

Sycamore¹³, Sandwich¹⁴, Hinckley¹⁵, Kirkland¹⁶, Maple Park¹⁷, Waterman¹⁸, Malta¹⁹, Shabbona²⁰ set their own zoning. Municipal zoning does not replace Health Department review of private septic systems³.

DeKalb County Health Department septic permits are required for installation, repair or modification; the department says the work must use Illinois-licensed septic installation contractors³. Applications need a soil evaluation and site drawing, and permits expire 1 year after issuance³. All installation components need inspection and final approval before covering⁵. Published fees are $415 for contractor-installed septic permits, $615 for the homeowner-installed category and $180 for septic inspections; ask Environmental Health how the homeowner category fits the licensed-installer requirement³. Debit and credit payments carry a 2.25% fee, with a $1.00 minimum³.

Residential systems need evaluation within 3 years of installation, then at least every 5 years; nonresidential systems have a 3-year recurring interval²¹. Aerobic treatment units need evaluation and maintenance at least every 6 months; sand filters and surface-discharge ponds at least annually²¹. USDA rates 0% of county soils as free from severe conventional-drain-field limitations, making site evaluation essential before buying²². Private wells also require a Health Department permit³.

Unincorporated DeKalb County allows overnight RV parking in residential neighborhoods, but that provision does not authorize RV residence; required accessory off-street parking facilities cannot be used to store motor homes, campers or other listed vehicles and materials². A recreational camp with RV or tent pads or electric and water hookups is a special land use in the A-1 Agricultural District, requiring a special use permit and siting that limits conversion of productive farmland².

We could not confirm general long-term RV residence, temporary private-land camping, tiny-home occupancy or minimum dwelling-size rules; ask Community Development about the parcel and proposed use¹. DeKalb County offers an interim special use for one manufactured home per lot for a dependent relative when hardship is established, rather than automatic permission for a second dwelling².

1. Ask Community Development to identify the parcel's zoning district, permitted use, minimum lot area, setbacks and height controls^1,2.
2. If the homesite needs a private well or septic system, apply to the Health Department; a septic application must include a soil evaluation and a scale drawing of the site and proposed facilities³.
3. If the parcel lacks a driveway or has only an agricultural field entrance, obtain an access permit from the appropriate road authority⁶.
4. Submit the complete building application, attachments and payment in hard copy; electronic submissions are not accepted⁷.
5. Wait for permit issuance before starting work, then keep construction inspections current so the permit does not expire⁴.
6. Obtain a certificate of occupancy or completion before using or occupying the finished building⁴.

Start with zoning and lot legality: district standards govern lot area, setbacks and coverage, and subdivision approval belongs to the Planning, Zoning and Development Committee and County Board^1,2. Check septic feasibility early because USDA rates 0% of county soils as free from severe conventional-drain-field limitations, and confirm whether a nearby sanitary sewer triggers connection^22,23. Verify legal road access because a parcel with no driveway or only a field entrance needs an access permit from the appropriate road authority with its building application⁶. For flood-hazard land, county-regulated work requires the applicable inspections and documentation². Budget for carrying costs: the effective property-tax rate is about 2.5%, and the median annual property-tax bill is about $5,889²².