In unincorporated St. Mary Parish, building permits come from the parish Planning & Zoning Department on the 5th floor of the courthouse at 500 Main Street, Franklin (337-828-4100 ext. 5280, permits@stmaryparishla.gov), and completed applications are filed in MGO Connect. Morgan City, Franklin, Patterson and Berwick run their own permit offices. The parish fee schedule charges $0.45 per square foot for a new house, with 12 inspections included.
What needs a permit in St. Mary Parish?
Chapter 5 of the parish code makes it unlawful to build, enlarge, alter, repair, move or demolish a building, or to change its use, outside the incorporated areas without a permit, and anyone placing a home, commercial building or other structure on a lot outside the municipalities must apply before work starts. The parish permit application covers:
Residential
- New houses, additions, renovations and repairs
- Attached patio covers and detached accessory buildings
- Whole-house generators and in-ground pools
- Elevating or relocating a house
- Manufactured and mobile homes
- Demolition
Commercial and institutional
- New buildings, renovations and additions
- Farm structures and commercial storage
- Signs and changes of occupancy
- Re-roofs, solar installations and cell towers
- Demolition
- Separate electrical, mechanical, plumbing and gas permits
State law adds two points. Because the parish issues permits, R.S. 37:3737(I), as re-enacted by Act 881 of 2026, requires it to permit and inspect roofing, including residential re-roofs, which the 2015 fee schedule does not list. R.S. 37:3738 bars a parish from enforcing the construction code on a detached residential accessory structure of 200 sq ft or less, unless it is in a hurricane-prone region with a design wind speed of 130 mph or more.
Who issues building permits in St. Mary Parish?
The parish code names the Director of Planning and Zoning as the parish building official, responsible for the state construction code outside every incorporated area; council minutes from March 2026 name Mandi LeBlanc as Planning & Zoning Director. Minutes of March 25, 2026 also show an inspector from the South Central Planning & Development Commission working on a parish building case. The department’s page lists its fax as 337-828-4092.
Short on time to read all of this?
Get a free quote →| Place (2025 population) | Building permits |
|---|---|
| Unincorporated parish | St. Mary Parish Planning & Zoning Department, Franklin courthouse; 337-828-4100 ext. 5280 |
| Morgan City (10,757) | City of Morgan City Planning and Zoning Department, 509 Second Street; 985-380-4716 |
| Franklin (6,224) | City of Franklin; applications go to the City’s building official, City Hall, 300 Iberia Street; 337-828-6303 (permits) |
| Patterson (5,565) | City of Patterson Building Department; plans are emailed to the City’s building official; City Hall, 1314 Main Street; 985-395-5205 |
| Berwick (4,455) | Town of Berwick; the town code requires permits from its building official; Planning & Zoning, 985-384-8858 |
| Baldwin (1,676) | The town publishes no permit page; it is registered with the state construction code council as an enforcing jurisdiction; town hall, 800 Main Street, 337-923-7523 |
The parish has an estimated 46,552 residents (Census 2025). Its sewerage rules give a second gate for every new building: after applying to the parish, the owner, a spouse or a person holding the owner’s power of attorney visits the parish sanitarian services office, and only when both offices approve is a temporary construction permit issued.
St. Mary Parish permit fees
Fees are set by section 5-60 of the parish code, adopted by Ordinance 2020 on September 23, 2015, and apply only in the unincorporated parish; parish council minutes through September 2026 show no change to them. Each fee includes a set number of inspections, and every inspection beyond that costs $75. Both parish checklists include payment of the plan review and permit fees, and the application says permit fees are non-refundable and non-transferable.
Not sure this scope needs a permit?
Get a free quote →| Permit | Fee | Inspections included |
|---|---|---|
| New house | $0.45 per sq ft | 12 |
| New residential accessory building with walls | $0.023 per sq ft as printed, $75 minimum, $500 maximum | 6 |
| Open-sided accessory structure, up to 500 sq ft / over 500 sq ft | $75 / $200, plus trade permits | 2, plus 2 per trade |
| Attached aluminum patio cover | $75 | 1 |
| Home renovation under $5,000 / $5,000–$10,000 / over $10,000 | $75 / $100 / $200 | 1 / 2 / 2 |
| New commercial or institutional building, addition, modular, commercial storage | $0.50 per sq ft, $500 minimum | 25 for new buildings; 2 for additions and modulars; 12 for storage |
| Commercial or institutional renovation | $0.25 per sq ft, $500 minimum | 12 |
| Trade permit (electrical, mechanical, plumbing, gas) | $125 | 2 |
| Whole-house generator / commercial generator | $200 / $1,000 | 2 / 4 |
| Manufactured or mobile home / skirting | $150 / $75 | 2 / 2 |
| In-ground pool | $200 | 3 |
| Structure elevation / house relocation | $500 / $250 plus trade permits | 6 / 2 |
| Residential demolition / commercial demolition | $100 / $250 minimum or $3 per $1,000 of cost | 1 / 1 |
| Flood, farm or zoning permit | $5 per $1,000 of construction cost | 2 |
| Commercial or institutional re-roof; commercial solar | $500 each | 3 |
| Change of occupancy / sign / pylon sign | $100 / $100 / $300 | 2 |
| New cell tower / co-location or antenna change | $4,000 / $1,500 | 6 / 4 |
| Each inspection beyond those included | $75 | – |
Electrical, plumbing, mechanical and gas work
The parish code requires separate permits for electrical, mechanical, plumbing and gas installations, each $125 with two inspections, filed before the work starts. Every subcontractor files its own job and schedules its own inspections; a homeowner cannot file a trade job on a subcontractor’s behalf, and a homeowner acting as builder must name the electrical, mechanical, plumbing and gas contractors on the application.
Rather talk it over?
Call 1-855-478-4290 →Sewer and water are handled by the state health office: an individual sewage system needs a work authorization and a final permit from the state health officer through the parish health unit (Department of Health, 985-385-7018). Commercial buildings also need a review letter from that office. Where a public sewer runs within 300 feet of the property line, the code requires a connection once the owner is notified.
Documents for a St. Mary Parish permit
Residential
- Completed application and a land use determination from Planning & Zoning
- Parcel number (Assessor, 337-828-4100 ext. 250) and legal description
- 911 address (985-395-3385)
- Flood determination letter and a scaled plot plan with setbacks
- Engineer’s drainage data form for lots over 1 acre, and a soil boring or compaction letter
- Health unit sewage form or community water and sewer deposit receipt
- Culvert permit from DOTD (337-828-0352) on a state road or from the local office on other roads
- Plans showing the designer and design wind speed
- State residential contractor licence and parish contractor registration, or a notarized homeowner affidavit
- Subcontractor list and copies of contracts
Commercial and institutional
- Application, land use determination and construction contract
- Parcel number, legal description and 911 address
- Engineer’s drainage data form and soil report
- Flood determination letter and plot plan
- Health unit review letter
- State Fire Marshal review letter
- State-licensed general contractor
- Complete stamped plans with riser diagrams, bearing original seals
- Subcontractor list and contracts
Rather not deal with the St. Mary Parish building department?
Get a free quote →How to get a parish permit in St. Mary Parish
Inside Morgan City, Franklin, Patterson or Berwick, apply to that city or town; for a Baldwin lot, ask the town hall first.
Call 911 for the address, the Assessor for the parcel number and Planning & Zoning for the flood determination and land use check.
Upload the application, plans and supporting documents and pay the plan review and permit fees.
Visit the parish sanitarian services office to approve the sewer and water arrangements.
The orange tag on the electrical box lets the utility give construction power; the temporary permit lasts six months.
After the final inspections and sanitarian approval, the parish issues the final permit, a green tag and the certificate of occupancy.
St. Mary Parish inspections
The parish lists 13 inspections for a new building: temporary pole, drainage preliminary grade, underground plumbing, foundation, mechanical rough-in, plumbing top-out, electrical rough-in, framing, electrical, plumbing and mechanical finals, final grade and building final. The new-house fee covers 12 of them, and each extra inspection is $75. The preliminary grade inspection comes after the forms are set and before any piping goes in, with ditches, culverts and silt fencing in place; on piling foundations it follows the piling. Gas work on a house is pressure-tested at top-out.
The permit and a copy of the approved plans must be posted on site, and sanitary facilities must be on site before work begins. Four inspections must be approved before walls are closed or insulated. Nobody may move in before the certificate of occupancy is issued, and the code fines occupancy without one $100 a day. A manufactured home is inspected for electrical, plumbing, tie-downs and skirting. Driven pilings need a notarized piling affidavit from the piling contractor naming the engineer of record.
Flood and site rules in St. Mary Parish
Flood elevation: the parish Unified Development Code adopts the flood insurance study and maps dated April 19, 2017. A new or substantially improved home in a special flood hazard area with a base flood elevation must have its lowest floor at or above that elevation, certified by a registered engineer, architect or land surveyor, and the parish permit checklist reminds applicants that mechanical equipment must also sit at the base flood elevation. In shallow-flooding AO zones without a depth number, the floor must be at least 2 feet above the highest adjacent grade.
Want this handled start to finish?
Get a free quote →Zoning: every permit starts with a land use determination under the Unified Development Code, which sets the zoning districts; the Planning & Zoning Commission and the parish council hear rezoning requests.
Utility tags: no utility may connect a structure or mobile home until the parish tag is on the electrical box: orange for temporary construction power, green after the final permit, and yellow for an affidavit where no permit is needed.
House numbers: the E911 district assigns numbers, which must be at least 4 inches tall and readable from the road.
Louisiana building code
Every Louisiana parish and municipality enforces the state’s Uniform Construction Code (R.S. 37:3737), adopted by the Louisiana Uniform Construction Code Commission: the 2021 International Codes with Louisiana amendments, in force since 1 January 2023, and the 2020 National Electrical Code, with the 2024 codes taking effect on 1 January 2027. A local government may set more stringent requirements only with the Commission’s approval, and the State Fire Marshal reviews plans for fire and life safety on all but one- and two-family dwellings. How the LSUCC works
Official St. Mary Parish permit resources
- St. Mary Parish Planning & Zoning Department
- St. Mary Parish permit applications in MGO Connect
- St. Mary Parish Code, chapter 5: building permits, requirements and fees
- St. Mary Parish Unified Development Code, Division 3.8: floodplain management
- St. Mary Parish Council minutes, March 11, 2026
- City of Patterson Building Department
- City of Franklin building permit application
- Town of Berwick Planning & Zoning
- Act 881 of 2026 (HB 1186): R.S. 37:3737 and 37:3738
- St. Mary Parish codes and resources
- Louisiana construction code editions
Inspections are where schedules slip.
Get a free quote →St. Mary Parish permit FAQs
Who issues building permits in St. Mary Parish?
The parish Planning & Zoning Department in the Franklin courthouse (337-828-4100 ext. 5280) for land outside the cities and towns. Morgan City, Franklin, Patterson and Berwick issue their own permits.
How much is a parish building permit for a new house?
$0.45 per square foot, which includes 12 inspections. Electrical, mechanical, plumbing and gas permits are $125 each, and extra inspections are $75.
Can I apply online?
Yes. The parish takes completed permit applications through MGO Connect.
Can I act as my own contractor?
The residential checklist accepts a signed, notarized homeowner affidavit, but the homeowner must list the electrical, mechanical, plumbing and gas contractors, and each of them files their own permits.
When will the power company connect my new home?
Only after the parish places its tag on the electrical box: an orange tag for temporary construction power and a green tag once the final permit is issued.
How high must a new house be built?
In a mapped flood zone with a base flood elevation, the lowest floor must be at or above that elevation on the April 19, 2017 maps, with mechanical equipment at the same level.
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More Louisiana permitting guides
This guide is provided by Alliance Permitting for general information about St. Mary Parish permitting. Requirements, fees, and procedures change; confirm details with the permitting authority before relying on them.