Off-grid site report
Prince William County, VA
38.7616, -77.6217 · 259 ft elevationRead 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.
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
- 1,379 kWh
JFMAMJJASOND
Weather1991-2020
- Precipitation
- 44 in/yr
- Snowfall
- 16 in/yr
- Heating degree days
- 4,700 (moderate)
- Frost-free season
- Apr 10 to Oct 31
How far help isstraight-line
- Hospital
Adventist HealthCare Germantown Emergency Center - 34.7 mi
- Fire station
New Baltimore Volunteer Fire and Rescue Company - 5.7 mi
- Hardware store
A.J. Carpet & Flooring - 2.2 mi
- Grocery
Safeway - 2.8 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 20168).
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.
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.