Off-grid site report
Henry County, IL
41.3022, -90.1966 · 817 ft elevationRead this before you act on anything below. This is my researched starting point for Henry County, IL, not legal advice and not a guarantee. Rules change, and the deciding facts on any specific parcel (setbacks, perc results, overlay districts, deed restrictions, road frontage) live at the county or town office, not in any database. Before you buy land or build, confirm the current rules directly with the local zoning and health offices - the sources on this page tell you exactly who to call.
The local rulesHenry County, IL
Zoning & raw-land occupancy
Varies locallyHenry County Zoning and Building Department oversees zoning only in unincorporated areas; density is tied to septic feasibility and any use change needs Zoning Board/County Board approval. Municipalities within the county have their own separate zoning. source
Dwellings, tiny homes & RVs
RestrictedCounty zoning ordinance sets minimum living area by district (600 sq ft in mobile home park/summer home districts, 825 sq ft in agricultural districts); tiny homes below these minimums and long-term RV residency aren't specifically addressed, so confirm with Zoning. source
Building permits & codes
Generally allowedHenry County enforces the International Building Code in unincorporated areas, and the Health Department must approve your plot plan (septic/water) before a building permit is issued.
Septic & composting toilets
Generally allowedThe Henry & Stark County Health Department permits private sewage systems under state IDPH codes, requiring certified soil testing, contractor plans, and final inspection; no county-specific composting toilet rule was found.
Greywater reuse
Unclear - verifyNo Henry County ordinance specifically addresses greywater reuse; it may be folded into the private sewage disposal permit, but this is inferred, not explicit. Ask the Health Department directly.
Rainwater harvesting
Unclear - verifyNo Henry County ordinance, zoning code, or Health Department page addressing residential rainwater harvesting was found. Not confirmed either way.
Private wells & water rights
Generally allowedThe Henry & Stark County Health Department issues well permits and inspections under Illinois Water Well Construction and Pump Installation Codes, per the county's Water Ordinance.
Living disconnected from utilities
RestrictedNo rule bans off-grid power generation, but county rules state a dwelling can't be occupied without adequate potable water and pressure, tying occupancy to an approved well/septic setup regardless of grid electricity status.
Sun30-year normals
- Peak-sun hours, annual average
- 4.8 hrs/day
- Worst month (sizes an off-grid array)
- 3.1 hrs/day
- Yearly output per 1 kW of panels
- 1,391 kWh
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Weather1991-2020
- Precipitation
- 38 in/yr
- Snowfall
- 25 in/yr
- Heating degree days
- 6,216 (cold)
- Frost-free season
- Apr 19 to Oct 18
How far help isstraight-line
- Hospital
Hammond-Henry Hospital - 11.1 mi
- Fire station
Cambridge Fire Department - 0.7 mi
- Hardware store
Menards - 15.0 mi
- Grocery
Hy-Vee - 9.3 mi
From OpenStreetMap. Road miles will be longer, often much longer in hill country.
Plan this spot
These open with this location's real numbers already filled in (ZIP 61238).
Size a solar systemHeat loss & insulationFirewood per winterRainwater harvestGarden sizePanel tilt
Looking at a specific parcel in Henry County, IL?The rules above are the jurisdiction. The land check runs the parcel itself: flood zone, soils and septic suitability, wetlands, slope, access, climate, and these verdicts, from a parcel number or coordinates.
Check a parcel →Share or save this report:New report
Sources: US Census Bureau geocoder; NLR PVWatts v8 (solar); NOAA NCEI 1991-2020 climate normals (nearest station) or Open-Meteo (ZIP-centroid) for weather; Open-Elevation; OpenStreetMap contributors. Public data retrieved Aug 22, 2026; agencies update their layers on their own schedules. Planning data, not a survey or legal advice.
New here, or not sure where this fits? Start here walks through the whole thing in order.