Tom Green County 2006 IRC, or San Angelo's 2021 IRC as adopted here

Barndominium Builders in Tom Green County, TX

Tom Green County is one of the few Texas counties with a residential building standard on its unincorporated land. On 8 June 2010 the Commissioners Court passed an order making Subchapter F of Chapter 233 applicable here, so a new house or duplex outside San Angelo has to conform to the International Residential Code and take three inspections. What it does not have is a building permit, a fee, a plan review or an inspector — the statute forbids all four, and the builder contracts the inspections privately. Almost everything else here is decided by the ground rather than the code. San Angelo holds 100,640 of the county's 120,602 people, which leaves about fourteen people to each of the 1,462 square miles outside the city limits. Roughly half the county reads caliche or limestone within about fifteen inches of the surface, which settles what a footing trench and a drainfield cost long before anyone opens a code book.

Tom Green County at a glance

County: Tom Green County
Population: 120,602
Where we build: San Angelo, Taylor County
Site visits: Site walks booked county-wide, San Angelo included

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Building conditions in Tom Green County

What actually changes from one Texas jurisdiction to the next: who issues the permit, whether the residential code is enforced there at all, what the structure has to be engineered to, and what the ground is like. These are the numbers your drawings have to satisfy.

Build conditions for Tom Green County, drawn from the sourced facts on this page. Every figure above is cited in the quick-facts panel below, with its source and vintage.

Tom Green County opted into the state building standard on 8 June 2010

Most Texas counties have no residential building code at all. This one does. On 8 June 2010 the Commissioners Court passed and approved an instrument headed Resolution to Make Subchapter F, Chapter 233, Texas Local Government Code, Applicable to Tom Green County. It resolves that, in accordance with Section 233.153, a new single-family house or duplex on a vacant lot in the unincorporated areas of Tom Green County shall substantially conform to the International Residential Code, and that a minimum of three inspections be performed. It passed unanimously, signed by County Judge Michael D. Brown and all four commissioners and attested under seal by County Clerk Elizabeth McGill. The order carries a blank order number and the county does not publish it on its website; it survives as an attachment to that day's minutes.

Resolution to Make Subchapter F, Chapter 233, Texas Local Government Code, Applicable to Tom Green County, passed and approved by the Commissioners Court 8 June 2010, attached to the minutes of that meeting — https://public.destinyhosted.com/agenda_publish.cfm?id=86647&mt=ALL&get_month=6&get_year=2010&dsp=min&seq=151

There is still no county permit, no fee, no plan review and no county inspector

Opting in does not give the county the machinery a city has. Local Government Code sec. 233.153(d)(1) says the subchapter may not be construed to require prior approval by the county before residential construction begins. Sec. 233.153(f) says a county may not charge a fee to defray the cost of enforcing the standards. Sec. 233.153(d)(2) does not authorise zoning. Sec. 233.154(a)(3) puts the three inspections on the builder, who contracts them privately from a licensed engineer, a registered architect, a professional inspector licensed by the Texas Real Estate Commission, a municipal plumbing inspector licensed by the state plumbing board, a building inspector employed by a political subdivision, or an ICC-certified residential combination inspector. Sec. 233.157(b) makes a violation a Class C misdemeanour, not a stop-work order.

Texas Local Government Code ch. 233 secs. 233.152, 233.153 and 233.154 — https://tcss.legis.texas.gov/resources/LG/htm/lg.233.htm

The code edition is a choice of two, and the builder is the one who names it

Sec. 233.153(a) and the county's own order both say construction shall conform to either the version of the International Residential Code published as of 1 May 2008 or the version applicable in the county seat. The county seat is San Angelo, which publishes its adopted codes on its own website and currently lists the 2021 IRC and the 2021 IECC. So the two limbs here are a 2008-vintage code and a 2021 one, and the statute is written as a disjunction rather than as a grant of authority to either. Sec. 233.154(b)(3) supplies the practical answer: the builder's pre-construction notice must state the version of the International Residential Code that will be used. The builder elects; nobody at the county rules on the election.

Texas Local Government Code ch. 233 secs. 233.152, 233.153 and 233.154 — https://tcss.legis.texas.gov/resources/LG/htm/lg.233.htm; City of San Angelo, Codes & Regulations, current adopted codes — https://www.sanangelo.gov/188/Codes-Regulations; Resolution to Make Subchapter F, Chapter 233, Texas Local Government Code, Applicable to Tom Green County, passed and approved by the Commissioners Court 8 June 2010, attached to the minutes of that meeting — https://public.destinyhosted.com/agenda_publish.cfm?id=86647&mt=ALL&get_month=6&get_year=2010&dsp=min&seq=151

The ten-acre septic exemption is dead here, in the county's own words

Tom Green County's septic order adopts 30 Texas Administrative Code Chapter 30 Subchapters A and G and Chapter 285 whole, with all future amendments, and then lists its own stricter rules in Section 10. That list has exactly one entry: Tom Green County does not exclude properties of 10 acres or greater from the permitting process, and all on-site sewage facilities in Tom Green County must be permitted and inspected by the authorized agent. Item (B) is blank. So buying a big tract does not buy anyone out of the septic permit here. The order also fixes the county's reach at all areas lying within Tom Green County except areas regulated under an existing order, and Section 12 records a 10 dollar state fee collected on each permit for the TCEQ Water Resources Management Account under Health and Safety Code Chapter 367.

Order Adopting Rules of Tom Green County, Texas for On-Site Sewage Facilities, secs. 6, 8, 9, 10(A), 12 and 13, adopted after public hearing 18 August 2014 — https://public.destinyhosted.com/tomgrmindocs/2014/COM/20140818_490/minutes/467_Order%20Adopting%20Rules%20TGC%20On-Site%20Sewage%20Facility.pdf

About half the county hits caliche or bedrock within roughly a foot of the surface

This is not clay country and the excavation story is the opposite of the one told further east. Measured against the USDA soil survey for Tom Green County, 27 soil components covering about 185,000 acres carry a petrocalcic horizon — cemented caliche — at an average depth of 38 centimetres, and 26 components covering about 300,000 acres hit lithic bedrock at an average of 33 centimetres. Together that is roughly 485,000 of the survey's 986,490 mapped acres with a hard layer inside about fifteen inches of the surface. Angelo clay loam is the single largest soil at about 335,000 acres, with Tarrant next at about 178,000. Good bearing, and a trencher's problem: footings, utility runs and a septic drainfield all have to get through it.

USDA-NRCS Soil Data Access, SSURGO survey area TX451 Tom Green County, legend, mapunit, component, chorizon, corestrictions and muaggatt tables, queried 1 September 2026 — https://SDMDataAccess.sc.egov.usda.gov

A joint airport zoning board covers both airfields, and the rule that reaches a house is glare

San Angelo Code sec. 2.07.251 creates the San Angelo-Tom Green County joint airport zoning board under Local Government Code sec. 241.014, by Ordinance 2018-121 of 2 October 2018. Sec. 2.07.252 gives it five members: two appointed by the commissioners court, two by the city council, and a fifth elected as chairman. The regulations it administers define airport as San Angelo Regional Airport/Mathis Field and Goodfellow Air Force Base — both fields, not one. The height limits are unlikely to touch a house: sec. 3-3-7 requires no permit for a structure under 75 feet in the horizontal and conical zones. The limb with no height floor is sec. 3-3-5, which forbids any use of land that results in glare in the eyes of flyers, makes airport lights hard to distinguish, or impairs visibility near the airport. On a metal building with yard lighting, that is the provision to think about.

San Angelo Code of Ordinances secs. 2.07.251 and 2.07.252 (Ord. No. 2018-121, sec. 1 (Exh. A), 2 October 2018) and ch. 12 Exhibit B, Airport Zoning Regulations, secs. 3-3-1, 3-3-2, 3-3-5 and 3-3-7 — https://library.municode.com/tx/san_angelo/codes/code_of_ordinances; Texas Local Government Code sec. 241.014 — https://tcss.legis.texas.gov/resources/LG/htm/lg.241.htm

Also worth knowing before you build in Tom Green County

Fourteen people to the square mile once you leave San Angelo: San Angelo is the only incorporated municipality in Tom Green County. The Census Bureau publishes the split directly: 100,640 people in the city in 2025 against a balance of county of 19,962, out of 120,602 in all. The city covers 60.06 square miles of the county's 1,522.32, so 1,462 square miles — about 96 percent of the land — sits outside every city limit and holds about 14 people to the square mile. That is the thinnest unincorporated density of any county page on this site. It also means the county is essentially flat in population: 120,002 at the 2020 census against 120,602 in 2025.
A groundwater district covers part of the county, and a small tract needs a drilling permit: The Lipan-Kickapoo Water Conservation District covers about 3,535 square miles across parts of Tom Green, Runnels and Concho counties, and its own management plan names San Angelo, Christoval and Grape Creek inside it. Its rules invert the usual expectation on small tracts: a well used solely for domestic or livestock use on 10 acres or less is not exempt under Water Code sec. 36.117 and a drilling permit must be applied for and approved before drilling. A genuinely exempt well is still not unregulated — the district's rules say an exempt well is exempt from permitting but not from preregistration, registration or the spacing rules, and preregistration has to be filed and approved before any drilling, reworking or re-equipping.
Well spacing is 330 feet, and it decides where the house can sit: District Rule 9.1 requires every well to be at least 330 feet from the nearest well or authorized well site and at least 50 feet from the nearest property line. For a well used solely for domestic and livestock use the property-line distance can drop to 10 feet, but only if the annular space between casing and borehole is cemented from the land surface to the top of the production layer. If the well goes in within 280 feet of a property line, wells along that line must be at least 660 feet apart. On a small tract those distances, the septic drainfield and the building envelope all have to be solved together rather than one at a time.
The plat application gates on a water-district letter and on your own commissioner: The county's subdivision application, revised May 2025, is reviewed by the Environmental Health Department rather than a planning office. It opens by asking whether the site is in the City of San Angelo annexation portion of the extraterritorial jurisdiction, and if it is, tells the applicant to stop and file the plat with the City of San Angelo instead. It asks whether the land is in the Lipan-Kickapoo Water District and, if so, requires a letter from the district authorising drilling. It requires a development and suitability study under 30 Texas Administrative Code sec. 285.4(c), written approval of road names and addressing from the CVCOG 911 addressing coordinator, and written notification from the applicant's own precinct commissioner before the application can even go to the County Clerk.
The floodplain order is keyed to the federal rule, and its elevation figure is not published: On 29 May 2012 the Commissioners Court moved to adopt an ordinance for the floodplain management measures that satisfy 44 Code of Federal Regulations sec. 60.3(d) of the National Flood Insurance Program regulations. It carried four to one, with the Precinct 3 commissioner voting nay. That motion names a federal regulation and no Water Code section at all. Environmental Health administers the permit and states that it determines how high new construction has to be elevated, but the adopted text is not posted, so any freeboard above base flood elevation has to be confirmed with that office at (325) 658-1038 rather than assumed. On the soil survey, about 61,000 of 986,490 acres are rated occasional or frequent for flooding.
The shop bay does not enlarge the drainfield: Septic capacity in Texas keys off living area, not total structure area. TCEQ form TCEQ-0235 asks for bedrooms and living area in square feet, and the Chapter 285 table pairs the two tests with an or. Some counties' authorised agents publish stricter definitions that pull a loft or an attached garage into living area. Tom Green County's order does not: its Section 10 list of stricter rules runs to a single item about the ten-acre exemption, and nothing in it touches living area. So on a 4,000 square foot barndominium with 1,800 square feet of three-bedroom living space and a 2,200 square foot shop, the design flow is the three-bedroom figure. There is also no percolation test anywhere in Texas — Chapter 285 classifies soil by texture and assigns a loading rate.
The court said no twice before it said yes: The deliberation record is unusually clear here. On 1 September 2009, the day H.B. 2833 took effect, the court considered approving an order to continue a Residential Inspection Program and require inspection reports to be filed with the County Clerk, per HB 2833. The minutes record: no action. On 1 June 2010 it considered the San Angelo Home Builders resolution supporting adoption of the terms of HB 2833. Again: no action. On 8 June 2010, with two Home Builders Association representatives at the table, it adopted the resolution — and the document attached to those minutes is the county's Subchapter F order itself. Across the whole 1995 to present minutes archive the string 2833 appears in exactly four items, all of them above, and nothing since rescinds it.
Expansive clay exists here but it is the exception, not the rule: The soil survey shows components with a horizon linear extensibility of 9 percent or more on about 15,094 acres — roughly 1.5 percent of the county's mapped area. The two that drive it are Tobosa, at about 11,130 acres with a peak linear extensibility of 17 and around 50 percent clay, and Lipan, at about 4,185 acres and a peak of 9.3. Everything else sits well below them: Angelo peaks at 7.5, Tarrant at 7.8, Mereta at 4.5, Cho at 1.6. Where the survey does show that shrink-swell ground, the IRC's own route applies — R403.1.8 hands expansive-soil foundations to the International Building Code section 1808.6 at a plasticity index of 15 or more, which is a Texas-licensed engineer's work.
The mineral estate is dominant, and a house that is not built yet is not protected: In Merriman v. XTO Energy the Supreme Court of Texas confirmed that the mineral estate is the dominant estate, and the accommodation doctrine did not save the surface owner even though, in the court's own words, his home and a barn are on the tract. The doctrine protects an existing surface use, so a house that has not been built cannot be weighed against a drilling plan. Tom Green County sits on the eastern flank of the Permian: the Railroad Commission counted 785 oil wells and 87 gas wells in the county as of February 2025, 558 and 60 of them producing. Whether the minerals under a particular tract were severed is a title question, not a county one — it is answered by the County Clerk's records and by the title commitment, not by anything the county publishes.
Two state requirements survive the gaps in county authority: The rural exemption in the Texas plumbing licence law does not reach plumbing performed in connection with new construction, so a Texas-licensed plumber is required on a new house here whatever the county does about inspections. And Health and Safety Code sec. 388.004 obliges a builder outside a municipality to certify that a new single-family house complies with the state energy standard. Tom Green County is climate zone 3B on both the pre-2021 and the 2021 Department of Energy county assignments, so unlike much of North Texas the zone does not shift with whichever code edition the builder elects under the county's order.
A septic variance here is an item on the Commissioners Court agenda: Section 13 of the county's septic order sends anyone aggrieved by a decision of the designated representative to the Commissioners Court, and the minutes show that route being used one property at a time. On 19 January 2010 the court authorised a one-time variance from the 100-foot septic-to-well setback for two named addresses. On 22 June 2010 it approved a septic variance at an address in Grape Creek for an irrigation well. On 31 May 2011 it authorised construction of an unoccupied building while a septic permit was still being processed. That is not a permit counter — it is a vote, per property, in open court.
The military-lighting power people expect a base town to have does not exist here: Goodfellow Air Force Base sits in Tom Green County, which invites the assumption that the county holds special powers over lighting near it. It does not. Local Government Code sec. 240.032(b-1) is the military limb of the county outdoor-lighting subchapter, and it applies only to a county with a population of more than one million that has at least five United States military bases, and to an adjacent county within five miles of a United States Army installation. Tom Green County had 120,602 people in 2025, has one installation, and that installation is Air Force. Both limbs fail. The other limbs of the subchapter are astronomical-observatory limbs keyed to McDonald, George and the Stephen F. Austin State University observatories, none of which is near here.
The county is the septic authority for the whole county, with no carve-outs: TCEQ's authorised agent register returns two rows for Tom Green County: the Tom Green County Authorized Agent, area served entire County, and TCEQ Region 08 in San Angelo. There is no river authority band, no health district, no city holding its own designation and no private contractor in the register, which is unusual — nine different arrangements appear across the counties on this site. The order matches the register: it applies to all areas lying within the county except areas regulated under an existing order. The work is done in-house by a TCEQ-certified designated representative and site evaluator at the Edd B. Keyes Building, 113 W. Beauregard Avenue, San Angelo.

Below the slab

The expensive surprises are in the ground, not the building

What moves a Texas budget is usually below grade, and it is soil rather than rock: shrink-swell clay. The Blackland Prairie and the Gulf Coast clays move enough between a wet season and a dry one to drive the foundation design across the state's largest markets, which is why several DFW cities require an engineer's seal on the foundation of every new house. Those are the same conditions that decide whether a septic field passes its soil and site evaluation, so the grading plan, the foundation and the drainfield get resolved together rather than one at a time. We price the dirt before we price the building.

What we build in Tom Green County

All nine of our services — kits, custom plans, post-frame and steel construction, site preparation, permitting and engineering, through to turnkey builds — are available across Tom Green County. What a project costs depends far more on the parcel than on square footage, so we work from your land rather than from a rate card.

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What a build looks like

Three stages every Tom Green County project passes through, from a raw parcel to a finished home. Site work first, because that is where the budget is decided.

Stage one

The parcel

Zoning, setbacks, flood zone and utility access get checked before anything is drawn.

Stage two

Pad and permit

Clearing, grading and a compacted pad, while the submittal works through Tom Green County.

Stage three

Frame to finish

Shell erected and dried in, then systems, insulation and interior finish through to CO.

Those are the rules for Tom Green County. Tell us what you want to build and we will draw it to them.

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Where we build around Tom Green County

Tom Green County and the rural land around it. The buildable acreage for a project this size usually sits outside the city limits, which is frequently what changes who issues your permit.

Our Tom Green County service area, covering Tom Green County and the surrounding rural acreage. This map marks the territory we serve, not a branch location.

Keep reading

The questions that usually come next once you know what Tom Green County allows.

Barndominium Cost Guide

Sourced per-square-foot ranges by tier and by size, with a calculator built on the same figures.

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Is It Legal in Texas?

Classification, zoning, the HOA gate, and why "nonresidential farm building" does not cover a home.

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How Long Does It Take?

Census build-duration data, and what actually sets the permit clock where you are building.

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Nearby areas we build in

Others we cover in this part of Texas. The permitting authority, the adopted design criteria and the zoning can all differ from one to the next.

San Angelo

Tom Green County

Taylor County

Building in Tom Green County: common questions

12 questions we get asked most often about building in Tom Green County. If yours is not on the list, ask it directly.

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Does Tom Green County have a building code for a house on unincorporated land?

Yes, and that makes it unusual. On 8 June 2010 the Commissioners Court adopted an order making Subchapter F of Chapter 233 of the Local Government Code applicable to Tom Green County, so a new single-family house or duplex on a vacant lot in the unincorporated area has to substantially conform to the International Residential Code and receive a minimum of three inspections. Most Texas counties never adopted such an order and have no residential building code at all.

So do I need a building permit from the county?

No. Local Government Code sec. 233.153(d)(1) says the subchapter may not be construed to require prior approval by the county before construction begins, and sec. 233.153(f) forbids the county from charging a fee to enforce the standards. There is no county building permit, no plan review and no county building inspector. The construction permit the county does issue is the on-site sewage facility permit, and a floodplain development permit applies where the land is in a mapped flood hazard area.

Which edition of the IRC applies?

The order tracks the statute and gives two: the version of the International Residential Code published as of 1 May 2008, or the version applicable in the county seat. San Angelo is the county seat and publishes its current adopted codes on its own site, which list the 2021 IRC. The statute is written as a choice rather than as a grant of authority to either, and sec. 233.154(b)(3) requires the builder's pre-construction notice to state the version that will be used. In practice the builder names the edition.

Who does the three inspections?

The builder hires them. Sec. 233.154(a)(3) lists who may perform them: a licensed engineer, a registered architect, a professional inspector licensed by the Texas Real Estate Commission, a plumbing inspector employed by a municipality and licensed by the state plumbing board, a building inspector employed by a political subdivision, or an individual certified as a residential combination inspector by the International Code Council. They fall at the foundation stage before concrete is placed, at framing and mechanical before covering, and on completion. The same inspector may do all three.

Is there a ten-acre exemption from the septic permit?

Not in Tom Green County. The county's septic order adopts the state rules whole and then lists its own stricter rules in Section 10. There is one entry, and it says the county does not exclude properties of 10 acres or greater from the permitting process, and that all on-site sewage facilities in the county must be permitted and inspected by the authorized agent. Acreage does not change the answer here.

Does the shop bay count against the size of the septic system?

No. Texas sizes a system on living area rather than on the whole footprint, and the state form asks for bedrooms and living area in square feet. An authorised agent is allowed to adopt stricter definitions, and some counties do pull lofts and attached garages in. Tom Green County's order does not — its list of stricter rules is a single item about the ten-acre exemption and says nothing about living area. So the workshop and the equipment bay do not enlarge the drainfield.

What does the ground do to a foundation and a drainfield here?

The dominant problem is a hard layer close to the surface rather than shrink-swell clay. The soil survey shows caliche at an average of about 15 inches over roughly 185,000 acres and bedrock at about 13 inches over roughly 300,000 more — around half the county between them. That is good bearing and slow digging, and it constrains where a conventional drainfield can go. Expansive clay does exist, on about 15,000 acres dominated by the Tobosa and Lipan soils, and where it is present the IRC hands the foundation to an engineer at a plasticity index of 15 or more.

Do I need permission to drill a water well?

Very likely, and it depends where you are. Part of the county lies in the Lipan-Kickapoo Water Conservation District, whose rules require preregistration to be filed and approved before an exempt well is drilled, reworked or re-equipped, and require a full drilling permit for a domestic or livestock well on 10 acres or less. Wells must be at least 330 feet from the nearest well and 50 feet from a property line, which for domestic use can drop to 10 feet if the annular space is cemented. The county's own plat application asks whether you are in the district and demands a letter from it authorising drilling.

Goodfellow Air Force Base is here. Does that restrict what I can build nearby?

There is a San Angelo-Tom Green County joint airport zoning board, created by city ordinance in October 2018 under Local Government Code sec. 241.014, with two of its five members appointed by the commissioners court. Its regulations define airport as both San Angelo Regional Airport/Mathis Field and Goodfellow Air Force Base. The height limits are unlikely to reach a house, since no permit is required for a structure under 75 feet in the horizontal and conical zones. The provision with no height floor is the use restriction that forbids glare in the eyes of flyers and lighting that is hard to tell apart from airport lights — worth raising with the airport manager before specifying a bright roof or tall pole lights near either field.

Does the county zone land?

No. A Texas commissioners court has no general zoning power, and sec. 233.153(d)(2) expressly does not authorise a court to adopt or enforce zoning under the building-standards subchapter. What actually restricts land here is different: recorded deed restrictions, the subdivision regulations the county adopted on 1 December 2020 and amended in 2024, the airport zoning overlay near the two airfields, and the septic rules that set a minimum lot size of half an acre on a public water supply and one acre on a private well.

I want to build outside San Angelo but inside its extraterritorial jurisdiction. Who reviews the plat?

The county's own application answers that first. Its opening question asks whether the location is within the City of San Angelo annexation plan portion of the extraterritorial jurisdiction, and if the answer is yes it says to stop and file the plat with the City of San Angelo planning department instead. If the answer is no, the plat is reviewed by the county's Environmental Health Department, needs written sign-off from the precinct commissioner, and then goes to the County Clerk and on to the Commissioners Court agenda.

Does anything about the Gulf Coast windstorm rules apply out here?

No. The catastrophe area is defined by the first tier coastal counties named in Insurance Code sec. 2210.003, and Tom Green County is not among them. The 2024 International Residential Code that 28 Texas Administrative Code sec. 5.4013 puts on construction in that area for catastrophe-insurance eligibility does not reach the Concho Valley, and no windstorm certificate is in play here.

Building in Tom Green County?

Start with the plan. Tell us what you want to build and we will draw it, then confirm what Tom Green County will actually let you put on the parcel and what wind load it has to meet. That conversation costs nothing.

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