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Off-grid site report

Prince William County, VA

38.6612, -77.3306 · 358 ft elevation
Read this before you act on anything below. This is my researched starting point for Prince William County, VA, 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 rulesPrince William County, VA

Zoning & raw-land occupancy
RestrictedPrince William County has countywide zoning under Chapter 32 of the County Code. The rural A-1 Agricultural district generally requires ten-acre lots (or one acre under a specific county provision with road frontage), and extra dwellings on ag land are limited to one per ten acres for farm use. source
Dwellings, tiny homes & RVs
RestrictedThe county's Building Development Division treats a tiny house on a permanent foundation as a standard single-family dwelling with occupancy limits tied to square footage. Tiny houses on wheels aren't separately addressed by the county, so treat them as RVs subject to the state's restriction on permanent occupancy until confirmed otherwise with Zoning Administration. source
Building permits & codes
Generally allowedPrince William County administers Virginia's Uniform Statewide Building Code locally through its Department of Development Services; even modest accessory structures over a certain size require a permit. source
Septic & composting toilets
Generally allowedThe Prince William Health District, under the Virginia Department of Health, issues septic permits and inspections for new construction. Composting toilets aren't addressed on a county-specific page, so this falls back to the state VDH framework. source
Greywater reuse
Unclear - verifyNo Prince William County or Health District page specifically addresses greywater reuse. It's reasonable to assume the state VDH framework applies through the local health district, but this is not confirmed; ask the Prince William Health District directly.
Rainwater harvesting
Unclear - verifyThe county's stormwater program addresses runoff and erosion control, not household rain barrel or cistern use specifically. Treat household rainwater harvesting as inherited from the state baseline until confirmed with the county. source
Private wells & water rights
Generally allowedPrivate wells are regulated by the Virginia Department of Health and administered locally through the Prince William Health District, which issues permits for new wells. Properties outside Prince William Water's service area, which includes much of the rural west, typically rely on private wells. source
Living disconnected from utilities
Unclear - verifyNo Prince William County ordinance was found requiring connection to electric utility service. However, occupancy still depends on Health District approval of septic/well systems and a building permit, so full off-grid disconnection isn't explicitly addressed one way or the other.

Open the full county page with sources →

Sun30-year normals

Peak-sun hours, annual average
4.8 hrs/day
Worst month (sizes an off-grid array)
3.5 hrs/day
Yearly output per 1 kW of panels
1,341 kWh
JFMAMJJASOND

Weather1991-2020

Precipitation
41 in/yr
Snowfall
10 in/yr
Heating degree days
4,199 (moderate)
Frost-free season
Apr 1 to Nov 7

How far help isstraight-line

Hospital
none within range
Fire station
Dale City Volunteer Fire Department
1.6 mi
Hardware store
Harbor Freight Tools
2.2 mi
Grocery
Giant
5.2 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 22192).

Size a solar systemHeat loss & insulationFirewood per winterRainwater harvestGarden sizePanel tilt

Looking at a specific parcel in Prince William County, VA?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.
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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.

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