Off-grid site report
Johnson County, IA
41.6483, -91.5380 · 643 ft elevationRead this before you act on anything below. This is my researched starting point for Johnson County, IA, 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 rulesJohnson County, IA
Zoning & raw-land occupancy
Varies locallyJohnson County's Unified Development Ordinance, administered by PDS, governs unincorporated land and requires a zoning/land-use compliance permit before building; incorporated cities like Iowa City or Coralville use their own zoning instead. source
Dwellings, tiny homes & RVs
Unclear - verifyNo official Johnson County page specifically addresses RVs or tiny homes as permanent dwellings; farm structures are exempt from the county building code, but that's narrow. Confirm with PDS directly. source
Building permits & codes
Generally allowedJohnson County has adopted the 2018 IBC and IRC (with radon appendix) plus state electrical, mechanical, and plumbing codes, administered by PDS; farm structures are exempt. source
Septic & composting toilets
Generally allowedJohnson County Public Health requires a construction/sewage permit before any private sewage system, including holding tanks, is installed, under the county's 2020 Private Sewage Disposal System Regulations within the state DNR framework. source
Greywater reuse
Unclear - verifyNo Johnson County ordinance specifically addresses greywater reuse; it likely falls under the same wastewater permitting framework or state DNR effluent rules. Ask Johnson County Public Health directly.
Rainwater harvesting
Unclear - verifyNo Johnson County or state page was found addressing rainwater catchment permits or restrictions either way; not confirmed.
Private wells & water rights
Generally allowedJohnson County Public Health's environmental health sanitarian issues Iowa DNR private well construction permits locally through the state's IWIS system, and offers free well water testing to residents. source
Living disconnected from utilities
Varies locallyNo county ordinance bans off-grid or disconnected living, but zoning, building, septic, and well permitting still apply to any habitable structure regardless of utility connections. source
Sun30-year normals
- Peak-sun hours, annual average
- 4.7 hrs/day
- Worst month (sizes an off-grid array)
- 3.0 hrs/day
- Yearly output per 1 kW of panels
- 1,362 kWh
JFMAMJJASOND
Weather1991-2020
- Precipitation
- 36 in/yr
- Heating degree days
- 6,379 (cold)
- Frost-free season
- Apr 20 to Oct 11
How far help isstraight-line
- Hospital
University of Iowa Stead Family Children’s Hospital - 0.9 mi
- Fire station
Iowa City Fire Station No. 1 - 0.9 mi
- Hardware store
Aero Rental and Party Shop - 0.3 mi
- Grocery
Natural Grocers - 0.4 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 52243).
Size a solar systemHeat loss & insulationFirewood per winterRainwater harvestGarden sizePanel tilt
Looking at a specific parcel in Johnson County, IA?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.