Off-grid site report
Mason County, TX
30.7485, -99.2319 · 1,565 ft elevationRead this before you act on anything below. This is my researched starting point for Mason County, TX, 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 rulesMason County, TX
Zoning & raw-land occupancy
Varies locallyMason County has no general zoning ordinance for unincorporated land; the Commissioners Court's Subdivision Regulations govern subdivided land development, not raw acreage. The City of Mason has its own zoning ordinance that applies only inside city limits/ETJ. source
Dwellings, tiny homes & RVs
Unclear - verifyNo county-adopted standard for tiny homes, minimum dwelling size, or RVs as dwellings was found for unincorporated land; not confirmed, ask the county. Inside the City of Mason, modular homes must have a state compliance decal and a permanent foundation per city code. source
Building permits & codes
Varies locallyThe City of Mason enforces building and zoning codes in-city via its Building Permits/Inspection Department. Unincorporated county land requires a Development Permit tied to floodplain/OSSF review, but no general countywide building code was confirmed. source
Septic & composting toilets
Generally allowedMason County, acting as a TCEQ-authorized agent, requires an OSSF permit for all new septic systems regardless of property size, per the county's OSSF Designated Officer rules. Composting toilets appear to fall under this same framework. source
Greywater reuse
Unclear - verifyNo standalone Mason County greywater rule was found; it is likely handled within the state OSSF/30 TAC 285 septic framework administered by the county. Confirm with the county's OSSF Designated Officer. source
Rainwater harvesting
Generally allowedNo Mason County ordinance restricts rainwater harvesting for domestic use; this follows the state's generally encouraging baseline.
Private wells & water rights
Varies locallyTexas's rule of capture applies to groundwater unless the land is inside a Groundwater Conservation District, and it is not confirmed whether any part of Mason County lies within a GCD. Verify with TWDB or the county before drilling. source
Living disconnected from utilities
Unclear - verifyNo Mason County ordinance requiring utility hookup was found for unincorporated land. The City of Mason has its own utility service ordinance that applies only inside city limits. source
Sun30-year normals
- Peak-sun hours, annual average
- 5.7 hrs/day
- Worst month (sizes an off-grid array)
- 4.5 hrs/day
- Yearly output per 1 kW of panels
- 1,582 kWh
JFMAMJJASOND
Weather1991-2020
- Precipitation
- 29 in/yr
- Snowfall
- 0 in/yr
- Heating degree days
- 2,420 (mild)
- Frost-free season
- Mar 27 to Nov 10
How far help isstraight-line
- Hospital
Heart Of Texas Memorial Hospital - 26.4 mi
- Fire station
Voca Volunteer Fire Dept - 18.3 mi
- Hardware store
- none within range
- Grocery
- none within range
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 76856).
Size a solar systemHeat loss & insulationFirewood per winterRainwater harvestGarden sizePanel tilt
Looking at a specific parcel in Mason County, TX?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 21, 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.