Off-grid site report

Washington County, TN

36.3093, -82.4065 · 1,745 ft elevation

Read this before you act on anything below. This is my researched starting point for Washington County, TN, 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 rulesWashington County, TN

Zoning & raw-land occupancy

RestrictedWashington County adopted a countywide Zoning Resolution in 1984, administered by the County Zoning Office and Regional Planning Commission, so raw land use is regulated by district, not left open like in unzoned TN counties. source

Dwellings, tiny homes & RVs

RestrictedThe county allows tiny homes and barndominiums anywhere single-family dwellings are permitted, but tiny homes must be site-built on a permanent foundation, effectively excluding tiny houses on wheels as permanent dwellings. source

Building permits & codes

RestrictedThe county's Zoning/Building office requires permits for new construction, additions, decks, and manufactured housing in unincorporated areas, and requires a septic and driveway permit as part of the application; incorporated towns handle their own permitting separately. source

Septic & composting toilets

RestrictedSeptic permitting is handled by the state agency TDEC, not the county health department, and the county requires that septic permit before issuing a building permit. source

Greywater reuse

Unclear - verifyNo Washington County ordinance on greywater reuse was found; this defers to the state TDEC/plumbing code framework, which is itself not clearly confirmed, so ask TDEC directly.

Rainwater harvesting

Generally allowedNo Washington County ordinance restricting rainwater collection was found in the zoning resolution, subdivision regs, or FAQ, so the general state baseline of allowing it appears to apply.

Private wells & water rights

Generally allowedWell drilling statewide, including in Washington County, is governed by the Tennessee Well Driller Supervision Program, which licenses drillers and pump setters; no separate county well ordinance was found. source

Living disconnected from utilities

Varies locallyThe county does not issue electrical permits itself, that goes through the State Fire Marshal's Office, but going off-grid on electric or septic doesn't exempt a dwelling from the county's building and zoning compliance requirements. source

Open the full county page with sources →

Sun30-year normals

Peak-sun hours, annual average: 4.9 hrs/day
Worst month (sizes an off-grid array): 3.7 hrs/day
Yearly output per 1 kW of panels: 1,359 kWh

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Weather1991-2020

Precipitation: 45 in/yr
Snowfall: 11 in/yr
Heating degree days: 4,387 (moderate)
Frost-free season: Apr 19 to Oct 21

How far help isstraight-line

Hospital Johnson City Medical Center: 1.2 mi
Fire station Ed Seaton Fire Station: 2.1 mi
Hardware store Harbor Freight Tools: 0.5 mi
Grocery Walmart Supercenter: 0.2 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 37605).

Size a solar system Heat loss & insulation Firewood per winter Rainwater harvest Garden size Panel tilt

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 21, 2026; agencies update their layers on their own schedules. Planning data, not a survey or legal advice.