Building permits, zoning and septic rules in Franklin County, Texas

No. Franklin County's own website lists no building, permit, inspection, or code-enforcement department; only a Septic Inspector and Fire Marshal appear among its offices¹. Texas law generally does not give counties authority to require a general building permit in unincorporated areas; the limited exceptions are fire-code permits, available only to a county with a population over 250,000 (or adjacent to one) and covering only commercial buildings, public buildings, and multifamily buildings of four or more units, plus optional residential standards a county may adopt within 50 miles of an international border¹⁰. Franklin County, with a population of about 10,735, isn't close to that fire-code population threshold, and no adoption of either limited program was confirmed^1,11. No official Franklin County source addresses an owner-builder exemption, which follows from there being no general building permit program for such an exemption to apply to¹².

No dedicated building or zoning office exists to call in Franklin County¹. For general county government matters, including plats and subdivisions handled by the Commissioners Court, start with the County Judge's Office at 903-537-4252, 200 N. Kaufman Street in Mount Vernon¹³. For septic, the county's own Septic Inspector & Designated Representative handles permits and inspections at (903) 537-8346, 204 Texas HWY 37 in Mount Vernon⁷.

Franklin County has no planning or zoning office and no general zoning ordinance for unincorporated land¹. Because the county has no zoning authority over unincorporated land, there is no county-set minimum lot size, setback, lot-coverage limit, or building-height rule, and no county zoning-based restriction on RVs, tiny homes, manufactured homes, accessory dwellings, or temporary camping². Mount Vernon is different: its municipal zoning ordinance applies to property inside the city and its extraterritorial jurisdiction to the maximum extent allowed by state or federal law³. Winnsboro, which lies partly in Franklin County, zones property inside its city limits under its own Zoning Ordinance, with a zoning-change process published on the city's website⁴. Subdivided land is also regulated even without county zoning: new plats and replats must go through two readings before the Commissioners Court, submitted as a single page with signatures, drawing, and field notes, and advertised in the newspaper twice before the first reading⁸.

Franklin County administers on-site sewage facility permits through its Septic Inspector and Designated Representative under the county's adopted OSSF rules and applicable TCEQ requirements⁵. The county publishes an application and checklist, but it does not publish the complete review, approval, inspection, and issuance sequence on that page, so ask the Septic Inspector what to submit and when to schedule inspection⁷. A permit and approved plan are generally required before covered OSSF work, and the county's designated representative inspects installations^6,14. Published fees are $375 for a residential system and $550 for a commercial one⁷. Only about 5.3% of Franklin County's soils have no severe limitations for a conventional drain field, so establish system feasibility before choosing a homesite¹¹. The conditional 10-acre exemption requires every listed condition, including a licensed site evaluation and at least 100 feet between every OSSF part and the property line, and it does not override a local permit requirement¹⁴.

Yes, as far as county zoning goes: Franklin County has no zoning authority over unincorporated land, so no county zoning rule restricts RV, tiny-home, or manufactured-home occupancy on an unincorporated parcel². Do not assume that answer applies around Mount Vernon, because the city's zoning ordinance covers property inside the city and its extraterritorial jurisdiction to the extent allowed by law³. Zoning is only part of the answer: plumbing or a septic system serving an RV, tiny home, or manufactured home still needs its own OSSF approval from the Franklin County Septic Inspector⁵. A private well may also need a permit if the parcel sits inside a groundwater conservation district; we could not confirm whether a particular Franklin County parcel falls within one⁹.

1. Confirm whether the parcel lies inside Mount Vernon, its extraterritorial jurisdiction or Winnsboro's city limits, where city zoning applies^3,4.
2. If you're subdividing or platting land, plan for two readings before the Commissioners Court, with the plat submitted as a single page carrying signatures, drawing, and field notes⁸.
3. Ask the Septic Inspector for the county's OSSF application and checklist, confirm the submission sequence, and arrange the required installation inspection^6,7.
4. Establish septic feasibility early because only about 5.3% of the county's soils lack severe limitations for a conventional drain field¹¹.
5. Ask the county's Emergency Management Coordinator about floodplain activity before placing improvements; Franklin County uses local flood-risk maps and monitors new development, and construction in the 100-year floodplain needs a development permit from the local floodplain administrator before work starts^15,16.
6. Check whether your parcel sits within a groundwater conservation district before drilling a well⁹.
7. If your driveway will connect to a state highway, submit TxDOT Form 1058 and give 24-hour notice before right-of-way construction¹⁷.

Test the soil for septic suitability before you commit: only about 5.3% of Franklin County's soils carry no severe limitations for a conventional drain field¹¹. Ask the Emergency Management Coordinator to check the county's locally generated flood-risk maps before choosing a building site; Franklin County monitors new development for floodplain activity¹⁵. A state water-agency review states that construction in the 100-year floodplain needs a floodplain development permit from the local floodplain administrator before work starts, and we could not confirm which Franklin County office issues it for a house¹⁶. Confirm whether the parcel is inside Mount Vernon or its extraterritorial jurisdiction, because the city's zoning ordinance reaches both areas to the extent allowed by law³. If the parcel was previously subdivided, check that the plat completed the Commissioners Court process⁸. Also verify well jurisdiction and access: a groundwater conservation district may regulate a well, while a driveway connecting to a state highway requires a TxDOT permit^9,17. Property tax runs near 0.9%, with a median annual bill around $1,944¹¹.