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

At a glance

Building permit

Not required in unincorporated Grimes County; the county does not inspect residential structures, but a Notice of Construction and Notice of Inspection must still be filed¹²

Zoning

None in unincorporated Grimes County; the City of Navasota has its own zoning districts⁸⁹¹⁰

Septic permits

Grimes County Environmental Services Division, the TCEQ-designated representative for the county⁶⁷

Floodplain permit

Required for all development in all unincorporated areas; $100 fee, and it must be the last permit issued⁴⁵

Driveway/culvert permit

Required through Road Department; published fee schedule shows $25 Type I / $50 Type II, though the online application form shows $26/$52⁵

RV / tiny home living

Unrestricted under county rules, since unincorporated Grimes County has no zoning ordinance¹¹

Minimum home size

None set by the county¹¹

Septic soil difficulty

Only 3% of county soils are free of severe limits for a conventional drain field¹²

Who to call

Contact details are copied from each office’s official page and were checked against it on September 23, 2026.

Do you need a building permit in Grimes County, Texas?

No general building permit is required for a home in unincorporated Grimes County, and the county does not inspect residential structures¹². That's typical for Texas: counties only get building-permit authority in narrow situations, such as a fire code for counties over 250,000 people (or adjacent to one) covering commercial and larger multifamily buildings, and neither applies to Grimes County's roughly 32,000 residents¹³¹⁴. Grimes County does layer one reporting requirement on top of that silence: the Commissioners Court adopted the 2021 International Residential Code effective December 18, 2024, and a builder must send the county a Notice of Construction and Notice of Inspection, even though the county itself performs no inspection³. Two other permits still apply regardless of building code: a Grimes County Development Permit for the property itself, and a Floodplain Development Permit if the land is in a mapped flood zone¹⁵⁴.

Who is the Grimes County building department, and how do you reach them?

There is no traditional building department with plan review and inspectors; Development Services is the office that collects the paperwork¹⁶. A Grimes County Development Permit, required for all development, must be completed by the property owner or their legal representative and can be submitted by email to [email protected] or in person at 270 FM 149 W., Anderson, Texas 77830¹⁶. The Notice of Construction and Notice of Inspection forms for the 2021 IRC go to the same email or address¹⁶. Development Services is directed by Shawn King; the County Engineer, Jonathan Steiber, also works out of the same office and doubles as Floodplain Administrator¹⁶¹⁷.

Does Grimes County have zoning?

No, unincorporated Grimes County has no zoning regulation at all⁸⁹. Texas gives counties zoning power only for a handful of special geographic areas — Padre Island beaches in Cameron or Willacy County, certain lakes, military zones, and similar limited districts — and Grimes County isn't one of them¹⁸. Inside the county, the City of Navasota is different: it has its own zoning districts and a formal process for zoning changes, conditional uses, PUDs and variances, so land inside Navasota's city limits follows city rules, not county silence¹⁰. Outside any city, the county sets no minimum home size, no minimum lot size, no setbacks and no building-height limit¹¹. That same silence means RVs, tiny homes, manufactured homes and temporary camping on your own land are unrestricted under county rules¹¹.

How do septic permits work in Grimes County?

Every septic system in Grimes County needs a permit from the county's own Environmental Services Division, which acts as TCEQ's designated representative for on-site sewage facilities⁶⁷. Statewide, Texas law requires a permit to construct, install, alter, extend or repair an OSSF, and Environmental Services inspects installation as part of that oversight¹⁹²⁰. Soils make this the real gatekeeper for building here: only 3% of Grimes County's land is free of severe limitations for a conventional drain field, so budget for a site evaluation and plan on many properties needing an aerobic or alternative system¹². Texas does offer a narrow exemption from OSSF permitting on tracts of 10 acres or more, but only if a licensed site evaluator or engineer signs off, it's the tract's only dwelling, every part of the system stays at least 100 feet from the property line, and effluent stays on the property¹⁹. Anything smaller, or missing any of those conditions, needs a permit from Environmental Services before you build¹⁹. If your land draws from a well instead, most wells in the county fall under the Bluebonnet Groundwater Conservation District, which requires registration for every well and an operating permit for non-exempt uses²¹.

Can you live in an RV or tiny home on your land in Grimes County?

Unincorporated Grimes County has no zoning ordinance restricting how you occupy your own land, so there's no county rule limiting RV or tiny-home living, and no minimum home size or lot size to meet¹¹. That freedom has real limits elsewhere, though: a Floodplain Development Permit still applies if your land sits in a mapped flood zone, for an RV, a tiny home or a conventional structure alike⁴. The county's own records don't establish a general certificate-of-occupancy requirement for private construction, though a Certificate of Compliance is required before electric utility service can be connected to certain floodplain, manufactured-home, RV or rental-community sites, so ask Development Services directly if that applies to your project⁴. If a Floodplain Development Permit applies to your parcel, apply for it after every other permit, since it must be the last one issued⁴.

Building a home in Grimes County: the steps, in order

First, confirm whether your parcel is in a mapped flood zone; if it is, apply for a Floodplain Development Permit last, after every other permit is issued, and budget the $100 fee¹⁷⁴⁵. Second, order a site and soil evaluation for your septic system early, since only 3% of the county's soils are free of severe limitations for a conventional drain field¹². Third, apply for your OSSF permit through Environmental Services before installing the system, unless your tract of 10 acres or more qualifies for Texas's site-evaluated exemption²²¹⁹. Fourth, submit a Grimes County Development Permit application, along with the Notice of Construction for the 2021 IRC, to Development Services¹⁶¹⁵. Fifth, if you need a driveway or culvert onto a county road, apply through the Road Department; the published fee schedule lists $25 for a Type I permit and $50 for a Type II permit issued after a notice of violation, though the online application form itself shows $26 and $52, so confirm the current fee before paying²³⁵. Sixth, send the county your Notice of Inspection once construction is complete; remember Grimes County itself does not inspect the structure¹⁶². If your driveway connects to a state highway instead of a county road, apply to TxDOT using Form 1058 and give 24-hour notice before construction begins²⁴.

What to check before you buy land in Grimes County

Soils are the biggest hidden cost here: with only 3% of the county's land free of severe septic limitations, budget for a site evaluation and possibly an engineered system before you count on a standard drain field¹². Water matters too — annual precipitation runs about 45 inches a year, but 16.2% of years bring severe drought, so a reliable well deserves real budget alongside septic²⁵²⁶. The land itself is flat and buildable, with 100% of the county at 15% slope or less, and about 30.3% forested, so grading is rarely the limiting factor²⁷²⁸. Check FEMA flood maps before you buy, since that's the one trigger for a required county permit and it must be the last one issued⁴. If the tract was recently split off a larger parcel outside a city, confirm it went through the county's development-permit and platting process, since a Grimes County Development Permit is required for all development¹⁵. Typical property tax runs about 1.1% effectively, with a median bill near $2,480 a year, against a typical home value around $358,256²⁹³⁰³¹.

Watch-outs

• Grimes County's published permit fee schedule lists driveway/culvert permits at $25 (Type I) and $50 (Type II), but the county's own online application form shows $26 and $52 — confirm the current fee with the Road Department before paying⁵.
• No official county source confirms a general owner-builder exemption from Notice of Construction, code-compliance reporting, or other requirements, so ask Development Services directly if you plan to build yourself³².
• The Floodplain Development Permit must be the last permit issued for a project — apply for septic, driveway/culvert, and development permits first⁴.

Sources

1. Grimes County Environmental Permits (2026 county census)
2. Development Services - Grimes County, TX, quoted and re-checked
3. Development Services - Grimes County, TX, quoted and re-checked
4. Floodplain Administrator - Grimes County, TX, quoted and re-checked
5. Grimes County Permits Fee Schedule, quoted and re-checked
6. Environmental Services - Grimes County, TX (2026 county census)
7. Environmental Services - Grimes County, TX, quoted and re-checked
8. Regarding Regulations in Grimes County (2026 county census)
9. Regarding Regulations in Grimes County, quoted and re-checked
10. City of Navasota Development Guide, quoted and re-checked
11. Texas law on county zoning and building authority
12. Share of soils without severe limits for a conventional septic drain field (USDA SSURGO): Bolthole Index county data
13. Local Government Code Chapter 233, County Regulation of Housing and Other Structures (Texas statewide rule), quoted and re-checked
14. County population: Bolthole Index county data
15. Development Services - Grimes County, TX, quoted and re-checked
16. Grimes County Development Services (grimescountytexas.gov)
17. Grimes County Floodplain Administrator (grimescountytexas.gov)
18. Local Government Code Chapter 231, County Zoning Authority (Texas statewide rule), quoted and re-checked
19. Getting a Permit for an OSSF - Such as a Septic System, quoted and re-checked
20. Environmental Services - Grimes County, TX, quoted and re-checked
21. Applications - Bluebonnet Groundwater Conservation District, quoted and re-checked
22. Grimes County Environmental Services Division (grimescountytexas.gov)
23. Grimes County Road Department (grimescountytexas.gov)
24. Section 4: Driveway Permits, Design, and Materials (Texas statewide rule), quoted and re-checked
25. Annual precipitation: Bolthole Index county data
26. Share of years in severe drought: Bolthole Index county data
27. Share of land at 15% slope or less: Bolthole Index county data
28. Wooded share of land: Bolthole Index county data
29. Effective property tax rate: Bolthole Index county data
30. Median property tax bill: Bolthole Index county data
31. Typical home value (Zillow): Bolthole Index county data
32. (2026 county census)

Written September 23, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.