Bolthole Index

Bexar County, Texas

Building permits, zoning and septic rules in Castle Hills, Texas

Castle Hills, Texas requires building permits for many residential projects and new construction through the city Permit Office.12 Castle Hills has its own zoning districts; Bexar County handles septic permits inside the city.34 Starting work without a required city building permit incurs a double fee.1

At a glance

Building permits
City building permits required for many residential projects; routine maintenance has exceptions1
Zoning
City zoning, with district-specific residential rules3
Septic permits
Bexar County Environmental Services requires septic permits4
Minimum lot area
A Single-Family District: 14,000 square feet5
Lot coverage
RR Rural Residential: buildings, structures and other impervious cover limited to 35%6
Owner-builder
City permits may be issued to residents personally performing work as permitted by state law7

Who to call

Building permits

Castle Hills Permit Office

City building permit applications, plan review and inspection questions

210-293-9675

[email protected]

209 Lemonwood Drive Castle Hills, TX 78213

Zoning

Castle Hills Code Enforcement

City zoning issues and ordinance compliance; address is City Hall

209 Lemonwood Dr., Castle Hills, TX 78213

Septic permits

Bexar County Environmental Services

Septic permits, installation inspections, renewals and existing-system registration

210-335-6700

612 Nogalitos San Antonio , TX 78204

Contact details are copied from each office’s official page and were checked against it on October 11, 2026.

Off-grid gear

Going off-grid in Castle Hills means bringing your own water and power. The kit we’d start with:

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Do you need a building permit in Castle Hills, TX?

Castle Hills requires building permits for many residential projects and new construction, while routine maintenance such as painting, minor roof repairs and asphalt-driveway repair or replacement is exempt.1 Castle Hills has adopted the 2021 ICC Codes and Energy Conservation Code 2020.8 Residents personally doing the work can receive city permits only as permitted by state law; doing the work yourself does not remove the city application process.7 Ask the Permit Office which building permit covers your scope before work begins, because Castle Hills doubles the fee for work started without a required permit.21

Who issues building permits in Castle Hills, and how do you apply?

The Castle Hills Permit Office receives building permit applications and answers building permit questions at 210-293-9675 or [email protected].2 The permit window accepts applications Monday through Thursday and Friday, with a shorter window on Friday.2 New construction, remodeling and additions require complete PDF plan renderings with the application; Castle Hills asks applicants to allow 10–15 working days for plan review.9 Driveway approaches, driveways and other flatwork require a site plan or survey with the city permit application.10 Include that work when discussing the project with the Permit Office.2

Does Castle Hills have zoning, lot-size limits and setbacks?

Castle Hills has city zoning districts, including A Single-Family, B Duplex, AAA Townhouse and RR Rural Residential.3 In the Castle Hills A Single-Family District, building lots must contain at least 14,000 square feet.5 The A district front setback is 40 feet or 20% of lot depth, whichever is greater, except lots under 15,000 square feet have a 35-foot minimum.11 A district side setbacks are 10 feet, or 20 feet on a corner street side; the rear setback is 20 feet, with a detached-accessory-building exception.11 A district buildings and structures may cover no more than one-third of lot area, while RR limits buildings, structures and other impervious cover to 35%.126 Ask Castle Hills Code Enforcement to identify the parcel’s district before sizing a house or accessory building.13

How do septic permits work inside Castle Hills?

Bexar County Environmental Services handles septic permitting inside Castle Hills: the county requires all on-site sewage facilities within Bexar County to be permitted.4 Bexar County also inspects septic installations at various stages, so a Castle Hills building permit does not replace the septic approval and inspection process.141 Texas generally requires a permit and approved plan to construct, alter, repair, extend or operate a septic system, and local authorities may impose stricter requirements.15 Do not assume the state acreage exemption overrides Bexar County’s stated permitting requirement; ask Environmental Services about the proposed system before installation.154

Can you live in an RV, tiny home or manufactured home in Castle Hills?

We could not confirm whether Castle Hills allows residential occupancy of an RV or tiny home on a private lot; ask Castle Hills Code Enforcement about the proposed dwelling and its zoning district.13 Castle Hills district rules do address manufactured-home placement and storage: A Single-Family and RR Rural Residential restrict manufactured homes subject to specified conditions.16 In the AAA Townhouse District, parking, storage or placement of manufactured homes and recreational vehicles is prohibited.16 Those placement and storage rules do not establish an RV occupancy allowance.16 We also could not confirm temporary camping, independent accessory-dwelling occupancy or a minimum dwelling floor area; request a parcel-specific answer from Castle Hills Code Enforcement.13

Building a home in Castle Hills: what steps come first?

  1. Ask Castle Hills Code Enforcement to confirm the zoning district, then fit the proposed home to that district’s lot and coverage rules.135126
  2. If the home will use septic, contact Bexar County Environmental Services about septic permitting before installation.4
  3. Submit the Castle Hills building permit application with complete PDF plans for new construction, remodeling or additions, allowing 10–15 working days for plan review.9
  4. Post the issued city building permit visibly when work begins and schedule the required construction inspections.917

For land outside Castle Hills city limits, use the Bexar County guide: the county’s ordinary residential building-permit answer concerns unincorporated land.18

Watch-outs

  • We could not confirm Castle Hills private-well requirements or an agricultural building-permit exemption; ask the Castle Hills Permit Office to identify the applicable approval and authority before committing to either project.2
  • Castle Hills subdivision proposals must meet the city’s floodplain development permit requirements where applicable; ask Code Enforcement which city floodplain approvals the parcel needs.1913

Sources

  1. Permits (Castle Hills), quoted and re-checked
  2. Castle Hills Permit Office (cityofcastlehills.com)
  3. Sec. 50-64. Area regulations (Castle Hills), quoted and re-checked
  4. Bexar County Environmental Services (bexar.org)
  5. library.municode.com (Castle Hills), quoted and re-checked
  6. Sec. 50-394. Area regulations (Castle Hills), quoted and re-checked
  7. Permits (Castle Hills), quoted and re-checked
  8. Permits (Castle Hills), quoted and re-checked
  9. Permits (Castle Hills), quoted and re-checked
  10. Permits (Castle Hills), quoted and re-checked
  11. Sec. 50-64. Area regulations (Castle Hills), quoted and re-checked
  12. Sec. 50-64. Area regulations (Castle Hills), quoted and re-checked
  13. Castle Hills Code Enforcement (cityofcastlehills.com)
  14. On-Site Sewage Facilities (Castle Hills), quoted and re-checked
  15. Getting a Permit for an OSSF - Such as a Septic System (Texas statewide rule), quoted and re-checked
  16. Sec. 50-67. Vehicle parking and storage (Castle Hills), quoted and re-checked
  17. Permits (Castle Hills), quoted and re-checked
  18. Bexar County FAQ - When is a building permit required in the unincorporated areas (2026 county census)
  19. Sec. 19-33. Standards for subdivision proposals (Castle Hills), quoted and re-checked

Written October 11, 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.

Answers from the rulebook for Castle Hills

Castle Hills’s own rules

  • Building permitRequired

    Many residential projects and new construction inside Castle Hills city limits.

    • Permits are not required for routine maintenance including interior and exterior painting, replacement of minor roof repairs, and repair or replacement of asphalt driveways.
    • Work started without a permit incurs a double fee.
    “Permits are required for many residential projects.”
  • Owner-builder exemptionConditional

    Residents personally performing permitted work inside Castle Hills city limits.

    • The city issues permits to a resident personally performing work only as permitted by state law.
    “If the resident is personally performing the work (as permitted by state law), permits are issued to the resident.”
  • Building code adoptedAdopted (with conditions)

    Building construction inside Castle Hills city limits.

    • The city page states adoption of the 2021 ICC Codes and Energy Conservation Code 2020.
    “The City of Castle Hills has adopted the ICC Codes, 2021, and Energy Conservation Code 2020.”
  • InspectionsRequired

    Permitted construction, new construction, renovations, and applicable repairs inside Castle Hills city limits.

    • New construction and renovations typically include foundation, framing, rough-in, top-out, TML, TOPS, and final inspections.
    • Many repair or replacement permits require inspection only upon completion.
    • Inspection requests must be called in no later than 2 p.m. for the next business day.
    “Many of the permits issued for repair or replacement will require inspections upon completion of the job only.”
  • Local zoningPresent

    Land inside Castle Hills city limits.

    • Chapter 50 is the city's zoning chapter and contains district regulations for A Single-Family, B Duplex, AAA Townhouse, and RR Rural Residential districts.
    “All building lots in this district shall contain not less than 14,000 square feet.”
  • Minimum lot sizeSpecified

    A Single-Family District inside Castle Hills city limits.

    • All building lots in the district must meet the stated minimum.

    minimum lot area: >= 14000 square feet

    “All building lots in this district shall contain not less than 14,000 square feet.”
  • SetbacksSpecified

    A Single-Family District inside Castle Hills city limits.

    • Front setback is 40 feet or 20 percent of lot depth, whichever is greater, except lots under 15,000 square feet have a 35-foot minimum.
    • Side setback is 10 feet, or 20 feet on a corner street side.
    • Rear setback is 20 feet, with a five-foot exception for detached accessory buildings.
    “There shall be a minimum front yard setback of 40 feet or 20% of the depth of the lot, whichever is greater, except where the area of a lot is less than 15,000 square feet the minimum front yard setback shall be 35 feet.”
  • Lot coverageSpecified

    A Single-Family District inside Castle Hills city limits.

    • Buildings and structures may not cover more than one-third of the entire lot area.

    maximum lot coverage: <= 33.333333 percent (one-third of lot area)

    “Buildings and structures on any one lot must not cover more than one-third of the entire lot area.”
    One more reviewed finding on this topic
    • Specified — RR Rural Residential District inside Castle Hills city limits.
      “Buildings, structures, and other impervious cover on any one lot must not cover more than 35 percent of the entire lot area.”
  • Manufactured homesLimited

    Manufactured-home placement or storage inside Castle Hills zoning districts.

    • Sec. 50-67 restricts manufactured homes in the A Single-Family District unless specified conditions are met.
    • Sec. 50-397 imposes the same type of restriction in RR Rural Residential.
    • Sec. 50-140 prohibits manufactured-home parking, storage, or placement in the AAA townhouse district.
    • Floodplain manufactured-home standards also apply where applicable.
    “No mobile home, manufactured home, trailer, semi-trailer, commercial or agricultural tractor, boat, recreational vehicle, bus, or truck (other than personal pickup trucks not designed or used for agricultural or commercial purposes) may be parked, stored, or placed in the AAA townhouse district.”
  • Septic inspectionRequired

    Installation of septic tanks inside Castle Hills city limits.

    • Bexar County conducts inspections at various points during installation.
    • Complaints or health and safety problems may also trigger an inspection.
    “All installations of septic tanks are inspected at various points during the installation.”
  • Subdividing landRegulated (with conditions)

    Subdivision proposals and manufactured-home parks or subdivisions inside Castle Hills city limits, at least in flood-hazard areas.

    • Proposals must comply with sections 19-2, 19-3, and 19-4.
    • Floodplain development permits under sections 19-8 and 19-23 are required where applicable.
    • Projects greater than 50 lots or five acres, whichever is lesser, require base-flood-elevation data if not otherwise provided.
    • Adequate drainage and protective placement of public utilities are required.

    threshold: 50 lots or five acres, whichever is lesser

    “All proposals for the development of subdivisions including the placement of manufactured home parks and subdivisions shall meet floodplain development permit requirements of section 19-8, section 19-23; and the provisions of Article III of this chapter.”
  • Driveway accessLimited

    Driveway approaches, driveways, and other flatwork inside Castle Hills city limits.

    • A site plan or survey must be submitted with a permit application for driveway approaches, driveways, and other flat work.
    “A Site Plan or Survey must be submitted with a permit application for the following:”
  • Permit processPublished (with conditions)

    Building permit applications inside Castle Hills city limits.

    • Applications are submitted at the Permit Office Monday through Thursday 8:00 a.m. to 4:00 p.m. and Friday 8:00 a.m. to 3:00 p.m.
    • New construction, remodeling, and additions require complete PDF plan renderings with the application.
    • Plan review generally takes 10–15 working days.
    • The permit must be visibly posted when work commences.
    “Please allow 10-15 working days for plan review.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Castle Hills or Bexar County directly.

  • Minimum dwelling size — Single-family and rural-residential dwellings inside Castle Hills city limits.
  • Building height — Residential and rural-residential buildings inside Castle Hills city limits.
  • Camping on your land — Temporary camping on private land inside Castle Hills city limits.
  • Tiny homes — Tiny-home occupancy inside Castle Hills city limits.
  • Accessory dwellings — Accessory-dwelling occupancy inside Castle Hills city limits.
2 more unanswered
  • Well permit
  • Agricultural exemption

Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.

Unanswered questions are usually a sign that Castle Hills publishes no rule on the point, not that none exists. Bexar County’s page lists the county offices to call.

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