Building permits, zoning and land rules in Smith County, Texas

Unincorporated Smith County has no general building-permit process for ordinary construction outside its subdivision and floodplain programs^1,8. Smith County uses an adopted fire code for new-construction and existing-building fire and life-safety inspections; that does not establish a comprehensive county building code⁹. The county floodplain permit form covers development in mapped Zones A or B, including construction, alterations, fill and manufactured-home placement¹. Inside Winona, building construction, alterations and repairs require the town's building permit¹⁰. Septic administration remains with Smith County's OSSF program through RTS Environmental LLC³.

The Smith County Engineer / Road & Bridge Department handles county rights-of-way and publishes the floodplain-development permit form¹¹. Reach Road & Bridge at 903-590-4800 or 135 SSE Loop 323, Tyler, TX 75702¹¹. Septic permitting questions go to RTS Environmental LLC at 903-630-4234 or smithcountyossf@yahoo.com³. Published county fees are $250 for subdivisions with roads, $100 without roads, and $25 for replats or lot-line adjustments¹². Manufactured-home rental community approval and floodplain development permits each cost $100; the schedule makes fees non-refundable and payable before final plat approval¹². Fire inspection fees vary by inspection type and building category⁸.

Unincorporated Smith County has no traditional countywide zoning ordinance². County zoning sets no minimum dwelling or lot size, setback, lot-coverage cap or height limit, and does not restrict accessory dwellings, manufactured homes, tiny homes, RV occupancy or temporary camping there⁴. Lindale and Winona administer their own zoning inside municipal limits^13,14. Septic administration stays with Smith County's OSSF program through RTS Environmental LLC³. Tyler also administers its own zoning, which does not apply to unincorporated Smith County¹⁵. Separate subdivision, floodplain and septic requirements still apply outside cities^1,3.

Smith County is the local OSSF authority, with RTS Environmental LLC administering the program as county contractor³. Installation or repair ordinarily requires evaluation, design and permitting through a licensed installer and registered sanitarian³. Septic and aerobic systems must ordinarily be maintained and inspected³. The county lists a minimum septic lot size of 0.5 acre, except for land platted before 1989³. A single-family dwelling on at least 10 acres needs no OSSF planning materials, permit or inspection only if the system causes no nuisance or groundwater pollution, every part is at least 100 feet from the property line, effluent stays on the property, and the home is the tract's only dwelling³. Only 27.5% of county soils lack severe conventional drain-field limitations, so arrange a site evaluation before choosing the homesite¹⁶.

For an RV or tiny home on unincorporated Smith County land, resolve sewage disposal and floodplain requirements before occupancy: private OSSF sanitation follows the county process unless the qualifying single-family dwelling exemption applies³. The large-tract exemption is not a general exemption for every off-grid arrangement; its conditions require a single-family dwelling as the tract's only dwelling³. Floodplain rules also cover manufactured-home placement and other development¹. A manufactured-home rental community needs a Certificate of Compliance before water, sewer, gas or electric service may begin⁸. Access from a state-maintained road requires TxDOT concurrence and an executed driveway permit before construction in the right-of-way^8,17.

1. Confirm the parcel is outside city limits; the county permit answer here concerns unincorporated Smith County¹.

1. Check the flood map and take proposed development in a regulated hazard area to Road & Bridge for floodplain review^11,18.

1. Arrange OSSF evaluation, design, and permitting through a licensed installer, registered sanitarian, and RTS Environmental^3,5.

1. Resolve access: county rules govern relevant culverts, while state-road access requires TxDOT concurrence and a driveway permit^7,8,17.

1. Ask whether fire and life-safety inspection applies to the project⁹.

1. Verify utilities, deed restrictions, easements, and plat status; manufactured-home rental communities need a Certificate of Compliance for utility service⁸.

Check flood exposure, septic suitability and road access before choosing a homesite. Smith County's floodplain permit form requires residential lowest floors, including basements, to be at least 1 foot above the expected 100-year flood level, with plans and calculations prepared and sealed by a registered professional engineer or land surveyor⁵. Agricultural work is not automatically exempt: qualifying unrestricted floodplain uses must avoid structures, fill, channel changes, obstruction and material storage¹⁹. Only 27.5% of county soils lack severe conventional drain-field limitations¹⁶. County culvert rules place pipe costs and ongoing maintenance on the owner but do not establish a universal driveway permit⁷. We could not confirm a general private-well permit or certificate-of-occupancy requirement; ask Road & Bridge which office should review the parcel.