Bolthole Index

Seminole County, Florida

Zoning, building permits and septic rules in Lake Mary, Florida

The City of Lake Mary, Florida, administers its own zoning code1, and its Building Division handles building permits, plan review and inspections inside city limits2. Septic permits for Lake Mary addresses come from the Florida Department of Health in Seminole County, not the city3. Outside city limits, Seminole County's rules apply instead.

At a glance

Zoning
Lake Mary adopts and administers its own zoning code1
Building permits
Issued by the City of Lake Mary Building Division2
Inspections and occupancy
Final inspection required before the city issues a certificate of occupancy4
Septic permits
Florida Department of Health in Seminole County5
Minimum lot size
Depends on district: 3 acres in A-1, 1 acre in R-CE67
Minimum house size
1,600 sq ft in R-CE; smaller in the R-1 districts89
Guest house / garage apartment
Permitted in R-CE10
Owner-builder
Florida law lets owners act as their own contractor; Lake Mary policy not confirmed11

Who to call

Building permits

City of Lake Mary Building Division

Building permits, plan review and inspections inside Lake Mary city limits

407-585-1366

911 Wallace Court, Lake Mary, FL 32746

Online permits →

Zoning

City of Lake Mary Community Development Department, Planning and Zoning Division

Zoning questions and development applications inside Lake Mary city limits

407-585-1360

911 Wallace Court, Lake Mary, FL 32746

Septic permits

Florida Department of Health in Seminole County, Environmental Public Health

Septic (onsite sewage) permits, site evaluations and inspections for Seminole County, including addresses inside Lake Mary

407-665-3604

[email protected]

400 W. Airport Blvd., Sanford, FL 32773

Contact details are copied from each office’s official page and were checked against it on October 23, 2026.

Off-grid gear

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

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Does Lake Mary, Florida have zoning, and what does it mean for lot size and setbacks?

Yes. The City of Lake Mary administers its own zoning code inside city limits, and parcels in the Big Lake Mary overlay district must also meet that district's standards, which take precedence over conflicting district rules1. The city publishes agricultural, rural estate and single-family districts12.

Lot size depends on the district. In the A-1 Agriculture district the minimum lot is 3 acres, measured above the mean high water line6. In R-CE Rural Country Estates it is 1 acre7. In the R-1A single-family district it is 10,890 square feet13.

In A-1 the setbacks are 25 feet in front, 30 feet in the rear, and a combined 20 feet on the sides14. Maximum building height is 35 feet in A-115.

Do you need a building permit in Lake Mary, and who issues it?

Building permits inside Lake Mary come from the city's own Building Division, which processes permits and provides plan review and inspection services under the Florida Building Code2. Seminole County's Building Division serves unincorporated land, so a Lake Mary address does not go to the county counter16.

New construction in the city needs a final inspection before the building official issues a certificate of occupancy17. The city also checks that any septic permit has passed its own final inspection first4.

We could not confirm the city's owner-builder rules. Florida law lets an owner act as their own contractor on a one- or two-family home for their own use, but the owner must sign the permit application and show direct, onsite supervision11. Ask the Building Division how it applies the exemption.

What are the minimum house sizes and guest-house rules in Lake Mary?

Minimum floor area varies by district, and garages, carports and porches do not count. R-CE requires 1,600 square feet8. Inside the Big Lake Mary overlay, A-1 land also requires 1,600 square feet18. The R-1A column of the single-family table sets 1,100 square feet9.

In R-CE, a guest house or garage apartment incidental to the use of the property is permitted10. We could not confirm accessory-dwelling rules for other Lake Mary districts, so ask Planning and Zoning before drawing plans19.

How do septic permits work inside Lake Mary?

Septic permits for addresses in Lake Mary are issued by the Florida Department of Health in Seminole County, which permits and inspects septic tanks on behalf of the state3. The path is a site evaluation by a qualified professional, then Form DEP 4015 submitted to the health department with the fee5.

Soils matter. Seminole County's soils rate poorly for conventional drain fields, so expect a site evaluation and possibly an engineered system20. We could not confirm whether sewer connection is required where city or county sewer is nearby, so ask the city's Building Division before you budget for septic.

Can you live in an RV or tiny home on your land in Lake Mary?

We could not confirm Lake Mary's rules for living in a recreational vehicle, camping on private land, or occupying a tiny home. The city's zoning code is the controlling document, and the Planning and Zoning Division is the office to ask19. Seminole County's temporary-RV approval for agricultural districts applies to unincorporated land, not to Lake Mary parcels21. Get a written answer from the city before parking an RV on a lot you plan to buy.

Building a home in Lake Mary: the steps, in order

  1. Confirm the parcel's zoning district and any Big Lake Mary overlay with the city's Planning and Zoning Division19.
  2. Check lot size and setbacks for that district against your plans1.
  3. If the lot is not on sewer, order a site evaluation and apply to the Florida Department of Health in Seminole County5.
  4. Apply for building permits through the city Building Division2.
  5. Schedule inspections as work proceeds; a final inspection comes before the certificate of occupancy17.
  6. Close out the septic final inspection so the city can issue the certificate of occupancy4.

What stays with Seminole County, and what to check before you buy

Septic permits come from the Florida Department of Health in Seminole County, and Florida requires a permit to install, repair or abandon a septic system22. Water well permits also sit outside city hall: Florida requires a permit from the appropriate water management district or its delegate23.

For land outside Lake Mary city limits, use the Seminole County page, because the county's rules apply only to unincorporated land24.

Seminole County's effective property tax rate is 0.7%25. Check flood zone and any homeowner association covenants before closing.

Watch-outs

  • Lake Mary's building code adoption, owner-builder policy and sewer-connection rule were not confirmed from the city's own code, so ask the Building Division before relying on county or state summaries2.
  • Zoning districts and dimensional standards apply only after the district rules in the city's zoning code are satisfied, and the Big Lake Mary overlay takes precedence over conflicting district provisions1.
  • Septic permits are not a city function: apply through the Florida Department of Health in Seminole County, and expect a site evaluation first5.

Sources

  1. Lake Mary Code of Ordinances § 154.57 R-1AAA, R-1AA, R-1A, and R-1B Single-Family Dwelling (American Legal Publishing) (Lake Mary), quoted and re-checked
  2. City of Lake Mary Building Division (lakemaryfl.com)
  3. Onsite Sewage and Disposal - Florida Department of Health in Seminole County (Lake Mary), quoted and re-checked
  4. Lake Mary Code of Ordinances § 150.06 Building Permits, Chapter 150 Building Code (American Legal Publishing) (Lake Mary), quoted and re-checked
  5. Onsite Sewage and Disposal - Florida Department of Health in Seminole County (Lake Mary), quoted and re-checked
  6. Lake Mary Code of Ordinances §§ 154.55 A-1 Agriculture and 154.56 R-CE Rural Country Estates (American Legal Publishing) (Lake Mary), quoted and re-checked
  7. Lake Mary Code of Ordinances §§ 154.55 A-1 Agriculture and 154.56 R-CE Rural Country Estates (American Legal Publishing) (Lake Mary), quoted and re-checked
  8. Lake Mary Code of Ordinances §§ 154.55 A-1 Agriculture and 154.56 R-CE Rural Country Estates (American Legal Publishing) (Lake Mary), quoted and re-checked
  9. Lake Mary Code of Ordinances § 154.57 R-1AAA, R-1AA, R-1A, and R-1B Single-Family Dwelling (American Legal Publishing) (Lake Mary), quoted and re-checked
  10. Lake Mary Code of Ordinances §§ 154.55 A-1 Agriculture and 154.56 R-CE Rural Country Estates (American Legal Publishing) (Lake Mary), quoted and re-checked
  11. 2025 Florida Statutes, Section 489.103, quoted and re-checked
  12. Lake Mary Code of Ordinances §§ 154.55 A-1 Agriculture and 154.56 R-CE Rural Country Estates (American Legal Publishing) (Lake Mary), quoted and re-checked
  13. Lake Mary Code of Ordinances § 154.57 R-1AAA, R-1AA, R-1A, and R-1B Single-Family Dwelling (American Legal Publishing) (Lake Mary), quoted and re-checked
  14. Lake Mary Code of Ordinances §§ 154.55 A-1 Agriculture and 154.56 R-CE Rural Country Estates (American Legal Publishing) (Lake Mary), quoted and re-checked
  15. Lake Mary Code of Ordinances §§ 154.55 A-1 Agriculture and 154.56 R-CE Rural Country Estates (American Legal Publishing) (Lake Mary), quoted and re-checked
  16. Seminole County Code Chapter 40 Building and Construction Appendix A, quoted and re-checked
  17. Lake Mary Code of Ordinances § 150.06 Building Permits, Chapter 150 Building Code (American Legal Publishing) (Lake Mary), quoted and re-checked
  18. Lake Mary Code of Ordinances §§ 154.55 A-1 Agriculture and 154.56 R-CE Rural Country Estates (American Legal Publishing) (Lake Mary), quoted and re-checked
  19. City of Lake Mary Community Development Department, Planning and Zoning Division (lakemaryfl.com)
  20. Share of soils USDA rates "not limited" for a conventional septic drain field (SSURGO). A strict rating: the median county is about 6% and a tenth of counties are 0%, so a low figure means most lots need a site evaluation or an engineered system, not that septic is impossible. Cite it only with that caveat: Bolthole Index county data
  21. Mobile Home Process and Requirements, quoted and re-checked
  22. OSTDS Construction Application (Florida statewide rule), quoted and re-checked
  23. Water Well Contractor Licensing and Permitting (Florida statewide rule), quoted and re-checked
  24. Codes and Regulations, quoted and re-checked
  25. Effective property tax rate: Bolthole Index county data

Written October 23, 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 Lake Mary

Lake Mary’s own rules

Rules another office applies inside Lake Mary

Lake Mary does not set these itself; the county, a health district or the state does, and they apply to every address inside its limits.

  • Who permits septicMixed

    Onsite sewage (septic) systems on land inside Lake Mary city limits, as administered in Seminole County.

    • Florida Department of Environmental Protection implements the state OSTDS statutes and rules since July 1, 2021.
    • Florida Department of Health in Seminole County (DOH-Seminole) issues permits and performs inspections for septic tanks in Seminole County.
    “under florida’s clean waterways act of 2020, county health department offices will continue to do the permitting and inspection for septic tanks.”
  • Septic permitRequired

    Septic system construction for a new home on land inside Lake Mary city limits, permitted through DOH-Seminole.

    • Application is DEP Form 4015 (Application for Construction Permit) with a site evaluation by a qualified professional.
    • Septic final inspection must be approved before a Lake Mary certificate of occupancy issues (see certificate_of_occupancy claim).
    “the florida department of health in seminole county’s (doh-seminole) environmental public health program issues permits for ostds in seminole county.”
  • Septic inspectionRequired

    Septic systems serving homes on land inside Lake Mary city limits, inspected through DOH-Seminole.

    • Since July 1, 2022, owners or contractors with owner authorization may hire a private provider to perform inspections of OSTDS, per the same DOH-Seminole page.
    • Inspection inquiries go to DOH-Seminole at 407-665-3239.
    “under florida’s clean waterways act of 2020, county health department offices will continue to do the permitting and inspection for septic tanks.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Lake Mary or Seminole County directly.

  • Building permit — Building permits for new residential construction inside Lake Mary city limits.
  • Owner-builder exemption — Owner-builder permitting inside Lake Mary city limits.
  • Building code adopted — Building code adopted for construction inside Lake Mary city limits.
  • Lot coverage — Lot coverage limits for homes inside Lake Mary city limits.
  • Living in an RV — Living in a recreational vehicle on private land inside Lake Mary city limits.
10 more unanswered
  • Camping on your land
  • Tiny homes
  • Manufactured homes
  • Off-grid sanitation
  • Well permit
  • Mandatory utility hookup
  • Agricultural exemption
  • Driveway access
  • Building in a floodplain
  • 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 Lake Mary publishes no rule on the point, not that none exists. Seminole County’s page lists the county offices to call.

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