Bolthole Index

Medina County, Texas

Building permits, zoning and land rules in Castroville, Texas

Castroville, Texas, in Medina County, handles residential building permits through city Community Development, with limited exceptions for smaller projects.1 Castroville also sets zoning by district and requires sewer connections where sanitary sewers are available, following city notice.23 For a parcel needing private septic, Medina County publishes a countywide septic permit requirement; ask Environmental Health to confirm the approval route for the city address.4

At a glance

Building permits
City building permits; limited residential exceptions, including accessory structures under 200 square feet without trade work.1
Zoning
City zoning applies; requirements depend on the parcel’s district.2
R-A lot size
One-family residential R-A: minimum lot area 12,000 square feet.5
R-A setbacks
Front 20 feet, side 10 feet, rear 25 feet; street-side yard minimum 15 feet, with additional restrictions possible.6
Sewer and septic
City sewer connection required where available after notice; Medina County states all septic systems require a permit.34
Manufactured homes
Mobile-home placement limited to land zoned to allow a mobile home park.7

Who to call

Building permits

Castroville Community Development Department

City building permit questions and applications; ask about historic-property review and the correct project approvals.

830-931-4090

[email protected]

703 Paris St. Castroville , TX 78009

Zoning

Castroville Community Development — Zoning

City zoning information, district map and zoning verification request.

Building permits

Castroville Community Development — Residential Permit Process

Residential plan submission, building inspections and certificate of occupancy requirements.

(830) 931-4090

[email protected]

703 Paris Street Castroville, Texas 78009

Septic permits

Medina County Environmental Health Department

County septic applications and inspections; confirm the permitting route for an address inside Castroville.

(830) 741-6195

1502 Avenue K 2nd Floor Hondo, Texas 78861

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 Castroville means bringing your own water and power. The kit we’d start with:

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Do you need a building permit in Castroville, TX?

Castroville requires building permits for residential remodeling involving roofs, siding, fixtures, doors or windows, and for accessory structures over 200 square feet.1 Accessory structures under 200 square feet are listed as exempt unless electrical, plumbing or mechanical work is involved; residential exceptions still must meet city zoning and building-code requirements.1 Ask Community Development to classify the specific work before ordering materials, especially when a small shed will have utilities.1 Castroville’s adopted codes include the 2012 International Residential Code and 2014 National Electric Code, with city ordinances controlling conflicts.8

Who handles building permits and zoning in Castroville?

Castroville Community Development coordinates city land and building development and accepts building permit applications at [email protected]; the office phone is 830-931-4090.9 For a new home, the city’s residential package calls for electronic building plans and a permit application, with fees paid before plan review.10 Castroville’s zoning page provides a zoning verification request, useful for resolving the district before designing a house.11 Historic properties may also need Historic Landmark Commission review, so ask Community Development about that review before altering an existing building.9

Does Castroville have zoning, lot-size rules and setbacks?

Castroville has city zoning regulating uses, building size and scale, parking and development; a parcel’s district determines the requirements.2 In Castroville’s one-family residential R-A district, the minimum lot area is 12,000 square feet, with minimum width of 80 feet and depth of 115 feet.5 R-A yards must be at least 20 feet in front, 10 feet at the side and 25 feet at the rear; the minimum side yard next to a public street right-of-way is 15 feet.6 Plat building lines and supplementary yard rules can require greater setbacks.6 R-A height is limited to 30 feet and 2.5 stories; these figures are district-specific, so do not apply them to every Castroville lot.12

How do sewer connections and septic permits work in Castroville?

Castroville requires a building’s owner or occupant to connect to city sewer where sanitary sewer exists or becomes available, within 30 days after notice from the building inspector or city health officer.3 Public-sewer connections require a written city permit and inspection before backfill.3 Medina County’s septic instructions state that all septic systems installed in the county require permits, licensed design and licensed installation; homeowners cannot install a system unless licensed as an OSSF installer.4 Before buying a Castroville lot without sewer, ask city Community Development about sewer availability and Medina County Environmental Health to confirm the city-address septic approval route.34 Do not assume a large tract removes the county’s stated septic permit requirement.4

Can you live in an RV or tiny home in Castroville?

We could not confirm Castroville’s general rule for residential RV occupancy, tiny-home occupancy or accessory dwellings; ask Community Development for the allowed use in the parcel’s zoning district before buying for that purpose.2 Castroville’s mobile-home rule allows placement only on land zoned for a mobile home park, so a vacant residential lot should not be treated as automatic permission for a mobile home.7 Castroville also has separate RV conditions in specified flood-hazard zones: an RV must satisfy the temporary-stay, highway-ready or permit/elevation/anchoring alternative.13 Those floodplain alternatives do not establish general permission to live in an RV on private land.13

Building a home in Castroville: what are the steps?

  1. Ask Castroville Community Development to verify the zoning district and the proposed residential use before preparing final plans.211
  2. Resolve city sewer availability and utility questions with Public Works, and confirm any private septic application with Medina County Environmental Health.3104
  3. Submit electronic plans and a building permit application to Community Development; pay the fees before plan review and provide an engineered foundation design or approval letter.10
  4. Arrange the required construction inspections and obtain a passing inspection before the next stage.10
  5. Obtain the city’s certificate of occupancy before moving into the building.10

What should you check before buying land in Castroville?

In Castroville special flood-hazard areas, new residential construction and substantial improvements must meet the city’s applicable elevation standards, including elevating the lowest floor to or above base flood elevation where required.13 Ask Community Development about floodplain requirements alongside the zoning review before fixing the house location.139 We could not confirm Castroville’s private-well rule or homeowner-as-contractor eligibility; resolve both with Community Development before relying on either option.9 For land outside Castroville city limits, use the Medina County guide: Medina County has no county zoning ordinance in unincorporated areas, while county septic and floodplain requirements remain separate.14415

Watch-outs

  • Castroville residential building permit exceptions do not waive zoning or building-code compliance.1
  • We could not confirm Castroville’s general RV or tiny-home occupancy rules; ask Community Development for a district-specific answer.2
  • Castroville’s R-A setbacks can be increased by plat building lines or supplementary yard regulations.6
  • City sewer availability can require connection after notice; do not budget for septic as an assured alternative.3

Sources

  1. Permitting (Castroville), quoted and re-checked
  2. Zoning (Castroville), quoted and re-checked
  3. Chapter 110, Section 110-83, Owner required to connect to sanitary sewer system (Castroville), quoted and re-checked
  4. Septic Tank Applications Permit, quoted and re-checked
  5. Comprehensive Zoning Ordinance (Castroville), quoted and re-checked
  6. castrovilletx.gov (Castroville), quoted and re-checked
  7. Chapter 22, Section 22-27, Buildings constructed elsewhere prohibited in the city; exceptions (Castroville), quoted and re-checked
  8. Chapter 22, Section 22-1, Technical codes (Castroville), quoted and re-checked
  9. Castroville Community Development Department (castrovilletx.gov)
  10. Castroville Community Development — Residential Permit Process (castrovilletx.gov)
  11. Castroville Community Development — Zoning (castrovilletx.gov)
  12. castrovilletx.gov (Castroville), quoted and re-checked
  13. Chapter 54, Section 54-77, Specific standards (Castroville), quoted and re-checked
  14. Texas law on county zoning and building authority
  15. What Type of Permits Are Required In Medina County?, 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 Castroville

Castroville’s own rules

  • Building permitLimited

    Residential construction and remodeling inside Castroville city limits.

    • The city lists residential exceptions, but those exceptions still must comply with the Comprehensive Zoning Ordinance and International Building Code.
    • Residential home remodels involving roof, siding, fixtures, and/or doors and windows require a building permit.
    • Accessory structures over 200 square feet require a permit.
    • Projects involving electric, plumbing, and/or mechanical work may require a permit even when an accessory structure is under 200 square feet.
    • Fees may apply for work without a permit and a stop-work order may be issued.

    accessory-structure threshold: < 200 square feet (Structures under 200 square feet are listed as exempt unless they have electric, plumbing, and/or mechanical work.)

    “No permits are needed for the following; however, they are still required to meet the Comprehensive Zoning Ordinance and International Building Code. These exclusions only pertain to residential permits. All other zonings must contact the Community Development Department. Residential home remodel (roof, siding, fixtures, and/or doors and windows) will require a building permit. If you are unsure if your project requires a permit, please contact Community Development as there are fees for work without a permit and a stop work will be ordered. [...] All accessory structures over 200 sq. ft. will be required to pull a permit.”
  • Building code adoptedAdopted

    Building construction inside Castroville city limits.

    • The city ordinance controls if it conflicts with the adopted codes or addresses a procedure addressed by an ordinance.

    International Building Code edition: 2012 · International Residential Code edition: 2012 · National Electric Code edition: 2014

    “National codes are hereby adopted by reference as though they were copied fully in this section, as follows: (1) 2012 International Building Code; (2) 2012 International Plumbing Code; (3) 2012 International Property Maintenance Code; (4) 2014 National Electric Code; (5) 2012 International Existing Building Code; (6) 2012 Fuel and Gas Code; (7) 2012 Mechanical Code; (8) 2012 International Residential Code; (9) 2012 International Energy Conservation Code; (10) 2012 International Fire Code.”
  • Local zoningPresent

    Land inside Castroville city limits; the city administers a Comprehensive Zoning Ordinance and zoning districts.

    • Site-specific requirements depend on the zoning district.
    • Special permits and zoning variances may be required in some cases.
    “The Zoning Ordinance establishes regulations for how sites can be used (such as residential, commercial, industrial), the size and scale of buildings, the amount of parking required, and other aspects of urban design and development throughout the city.”
  • Minimum lot sizeSpecified

    One-family residential R-A district inside Castroville city limits.

    • The ordinance table also specifies minimum lot width of 80 feet and minimum lot depth of 115 feet.

    minimum lot area: 12000 square feet

    “R-A 20 10* 25 12,000 30 2½ Stories 80 115”
  • SetbacksSpecified

    One-family residential R-A district inside Castroville city limits.

    • The table footnote requires a 15-foot minimum side yard adjacent to a public street right-of-way.
    • Supplementary yard regulations and plat-established building lines may require greater setbacks.

    minimum front yard: 20 feet · minimum side yard: 10 feet (15 feet adjacent to public street right-of-way) · minimum rear yard: 25 feet

    “R-A 20 10* 25 12,000 30 2½ Stories 80 115 [...] * A minimum side yard of 15 feet shall be provided adjacent to public street right-of-way.”
  • Building heightSpecified

    One-family residential R-A district inside Castroville city limits.

    • Maximum height is expressed as both feet and stories.

    maximum height: 30 feet · maximum height: 2.5 stories

    “R-A 20 10* 25 12,000 30 2½ Stories 80 115”
  • Manufactured homesLimited

    Placement and occupancy of manufactured or mobile homes inside Castroville city limits.

    • A mobile home may be placed only on a lot or parcel zoned to allow a mobile home park.
    • The section also addresses building-code compliance and exceptions for certain temporary structures and components.
    “nothing in this section shall prohibit the location of a mobile home constructed after June 15, 1976, provided such mobile home is placed only on a lot or parcel of land located within the city which has been zoned so as to allow the operation of a mobile home park”
  • Mandatory utility hookupSewer (with conditions)

    Buildings inside Castroville city limits where sanitary sewers exist or later become available.

    • Connection must be made within 30 days after notice from the building inspector or city health officer.
    • Connection is made under supervision of the building inspector.
    • A written city permit is required for public-sewer connections, and connections must be inspected before backfill.

    connection deadline after notice: 30 days

    “Any owner or occupants of any building situated in any connection within the city where sanitary sewers exist and where they may hereafter exist is hereby required to construct or cause to be constructed suitable water closets on such property and connect the same with the city sewer under the supervision of the building inspector. Such connection must be made within 30 days after notice from the building inspector or city health officer has been served upon such owner or occupant by first class mail notifying him to make such connection.”
  • Building in a floodplainRequired

    Residential, nonresidential, manufactured-home, recreational-vehicle, subdivision, and other development in Castroville special flood-hazard areas.

    • Residential construction must elevate the lowest floor, including basement, to or above base flood elevation where required.
    • Professional certification is required for applicable elevation or floodproofing standards.
    • Recreational vehicles in specified zones must be on site fewer than 180 consecutive days, be fully licensed and highway-ready, or meet permit, elevation, and anchoring requirements.
    • Manufactured homes have additional elevation and anchoring requirements.

    RV maximum stay under temporary exception: < 180 consecutive days (Alternatively, the RV may be fully licensed and ready for highway use or meet applicable permit, elevation, and anchoring requirements.)

    “In all areas of special flood hazards where base flood elevation data has been provided as set forth in (i) division 2, section 54-43 , (ii) division 3, section 54-62 , (iii) division 4, section 54-78 , the following provisions are required: (1) Residential construction. New construction and substantial improvement of any residential structure shall have the lowest floor (including basement), elevated to or above the base flood elevation. [...] (5) Recreational vehicles. Require that recreational vehicles placed on sites within Zones A1-30, AH, and AE on the community's FIRM either: a. Be on the site for fewer than 180 consecutive days, or b. Be fully licensed and ready for highway use, or c. Meet the permit requirements of division 3, section 54-63 and the elevation and anchoring requirements for "manufactured homes" in paragraph (4) of this section.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Castroville or Medina County directly.

  • Owner-builder exemption — Homeowner acting as contractor for construction inside Castroville city limits.
  • Minimum dwelling size — Residential dwellings inside Castroville city limits.
  • Lot coverage — One-family residential R-A district and other districts inside Castroville city limits.
  • Living in an RV — Long-term or residential RV occupancy on private land inside Castroville city limits.
  • Camping on your land — Temporary camping on private land inside Castroville city limits.
9 more unanswered
  • Tiny homes
  • Accessory dwellings
  • Who permits septic
  • Septic permit
  • Septic inspection
  • Well permit
  • Agricultural exemption
  • Driveway access
  • Short-term rentals

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 Castroville publishes no rule on the point, not that none exists. Medina County’s page lists the county offices to call.

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