Texas · Counties · Williamson County

Williamson County

What it takes to put a carport, garage, barn or RV cover on your property in Williamson County, Texas. Permit authority, wind speed, and who to call.

Georgetown · county seat South and Central Texas 752,827 people · 1,116 sq mi VERIFIED 09 / 2026
COUNTY MAP
outline + city dots
slot, not yet drawn
DO YOU NEED A PERMIT?
No, not from the county

Williamson County states that Texas counties have not been given general zoning authority by the legislature, so the county does not deal with most site plans or issue building permits, except for health and safety matters handled through the Williamson County and Cities Health District. The county permits it does issue on unincorporated land are a driveway permit for a connection to a county-maintained road, subdivision and certificate of compliance work through the County Engineer, and a Fire Marshal construction permit. That Fire Marshal permit reaches public buildings, commercial establishments and multi-family dwellings of four or more units, not a residential carport or garage.

Texas counties have no general zoning power. Outside city limits there are no county setbacks, no lot coverage rule and no design review, so nobody at the county can tell you where on your land the building goes.

This is the county's own description of its authority. It does not cover land inside Georgetown, Round Rock, Cedar Park or any other city limit or extraterritorial jurisdiction, and it is not a septic or floodplain answer. A driveway permit is still required if the delivery changes an access point onto a county road.

  • Texas counties have not been given general zoning authority by the state legislature, so the County does not deal with most site plans or issue building permits except for health and safety issues handled by the Williamson County and Cities Health District.source ↗ · read 2026-09-09 · archived copy ↗
  • A Driveway Permit is required to construct a proposed driveway or modify an existing driveway connecting to a county-maintained roadway.source ↗ · read 2026-09-09 · archived copy ↗
  • public buildings, commercial establishments, and multi-family residential dwellings consisting of four or more unitssource ↗ · read 2026-09-09 · archived copy ↗
DESIGN WIND SPEED

Regional band for south and central texas. Wind speed follows your address, not the county line, so this is context and not a site figure.

110 – 130 mph
NOT SITE VERIFIED
90110–130130160 MPH

ASCE 7, Risk Category II. Look up your exact address →

County zoning
None
Statewide. Texas counties hold no general zoning power.
Windstorm certification
Not required
Williamson is inland. Only the 14 coastal counties need a TDI WPI-8.
Floodplain administration
Not verified
We have not confirmed who administers FEMA floodplain permits here. Call the county before you pour.
Septic / OSSF setback
Not verified
If your slab lands near a septic field, the OSSF authority has a say. Ask when you call.
SPONSOR · 970×120AD 1 OF 2
TEXAS DEALER OR CONTRACTOR
photo + one line, always labeled
[email protected]

Cities and communities in Williamson County

Inside city limits the city's rules apply on top of the county's, and cities do zone. We have not yet read each city's ordinance, so every row below is marked unverified.

AustinRules not verified
Cedar ParkRules not verified
CouplandRules not verified
FlorenceRules not verified
GeorgetownRules not verified
GrangerRules not verified
HuttoRules not verified
JarrellRules not verified
LeanderRules not verified
Liberty HillRules not verified
Round RockRules not verified
SchwertnerRules not verified
TaylorRules not verified
ThrallRules not verified
WalburgRules not verified
WeirRules not verified
ALL ZIP CODES · 27
765117652776530765377657376574765777657878613786157862178626786287863378634786417864278664786657867478681787177872778728787297875078759
WHO TO CALL

Williamson County Engineer / Road and Bridge Division

3151 SE Inner Loop, Georgetown, TX 78626
Call (512) 943-3330 County permit page ↗
Ask them three things: do I need a permit to put up a carport here, is my site in a floodplain, and how far from the septic field.
CHECK YOUR EXACT SITE

Opens ATC Hazards by Location, the source we use for wind, snow and seismic values.

NEIGHBORING COUNTIES
SPONSOR · 300×250AD 2 OF 2
TEXAS DEALER OR CONTRACTOR
photo + one line, always labeled
[email protected]
Call Williamson County