The City of Key Colony Beach, Florida runs its own zoning and issues its own building permits; any project estimated above $1,000 needs one12. Living in an RV or travel trailer is prohibited, even for one night3. Septic permits in Monroe County come from the county health department, not the city building office4.
At a glance
- Building permit
- Required from the city for work over $1,000; cosmetic maintenance on single-family homes and duplexes is exempt2
- Zoning
- City Land Development Regulations with R-1A, R-1B, R-3, RH and B-1 districts1
- Septic
- Permits come from the Florida Department of Health in Monroe County; the city's own role is unconfirmed4
- RV living
- Prohibited, even for one night3
- Camping
- Unlawful on public or private property in the city5
- Manufactured homes
- Installation not permitted6
- Owner-builder
- One new single-family permit in 5 years, with the owner on site7
- Minimum home size
- 1,000 sq ft in R-1B; 1,200 sq ft in R-1A89
Who to call
Building permits
City of Key Colony Beach Building Department
Building permit intake, plan review, inspections, certificates of occupancy, contractor registration and floodplain management inside Key Colony Beach
600 West Ocean Drive, Key Colony Beach, FL 33051
Septic permits
Florida Department of Health in Monroe County
Septic (OSTDS) permitting and inspection for Monroe County
Contact details are copied from each office’s official page and were checked against it on October 16, 2026.
Off-grid gear
Going off-grid in Key Colony Beach means bringing your own water and power. The kit we’d start with:
- Water Crystal Quest Filter any source — well, rain, or creek — to drinking-clean.
- Power Bluetti Solar generators and home battery backup for living off the grid.
- Septic Soil percolation test kit Run your own perc test before paying an engineer — the first thing a septic office asks about.
- Water Well water test kit Bacteria, nitrates, hardness — know what the well on a parcel is really pumping.
These are affiliate links — we may earn a commission, at no cost to you. As an Amazon Associate, Bolthole Index earns from qualifying purchases.
Do you need a building permit in Key Colony Beach, Florida?
Yes, for almost any real work. Inside Key Colony Beach, a project with an estimated cost above $1,000 requires a building permit, and the building official sets the cost estimate2. Fences and electrical, plumbing or mechanical additions also need permits, and starting work before the permit carries a penalty fee2. Cosmetic maintenance such as painting, roof coating, plastering and stucco on a single-family home or duplex is exempt2.
The city adopts the Florida Building Codes and applies the most restrictive code where they differ, with its own flood-provision amendments10. All permitted work must pass inspection, owner-built work included11. Monroe County's separate exemption for small repairs applies only to unincorporated Monroe County, not inside the city12.
Who issues building permits in Key Colony Beach, and how do you reach them?
The City of Key Colony Beach Building Department issues building permits inside the city. Its services include permit intake, plan review, inspections during construction, certificates of occupancy, contractor registration and floodplain management13. Call (305) 289-1212, ext. 3, or email [email protected]; City Hall is at 600 West Ocean Drive13.
A reader inside city limits who calls the Monroe County Building Department in Marathon has the wrong office: that department serves unincorporated Monroe County12. The county is still the right call for septic permits and for the county-maintained rights-of-way it controls414.
Does Key Colony Beach have zoning, and what does it mean for RVs, lot size and setbacks?
Yes. Key Colony Beach administers its own Land Development Regulations, with residential, R-3, RH and B-1 districts1. Monroe County's planning department covers only unincorporated areas, so its zoning does not govern city lots15.
- R-1B: minimum lot of 6,000 sq ft and 60 ft wide; yards of 25 ft front, 7.5 ft each side and 25 ft rear; 1,000 sq ft minimum home16178.
- R-1A: minimum lot of 7,500 sq ft and 75 ft wide; yards of 25 ft front, 8.5 ft each side and 25 ft rear, except 50 ft from mean high tide along Vaca Cut; 1,200 sq ft minimum home18199.
Height in both districts is 30 ft or 2 stories, whichever is less, where living space sits below base flood elevation; 40 ft applies when all habitable space is above it2021. Installing a manufactured home is not permitted in the city6.
Can you live in an RV, tent or tiny home in Key Colony Beach?
No for RVs and camping. Key Colony Beach prohibits using an RV or travel trailer as a residence, even for one night3. A resident may park one licensed motor home or travel trailer on their own property or an adjacent vacant lot they own or lease, but not occupy it3. Camping, tenting or sleeping in the open is unlawful on any public or private property in the city, apart from a minor child camping occasionally in the owner's back yard5.
We could not confirm any city rule for tiny homes or accessory dwelling units. Florida law lets a local government adopt an accessory-dwelling ordinance but does not require one22, so ask the Building Department before planning a second unit.
How do septic permits and sewer connection work in Key Colony Beach?
Monroe County is not one of the 16 counties where the state Department of Environmental Protection issues septic permits, so the county health department handles septic permitting and inspection4. The Florida Department of Health in Monroe County, at 305-293-7500, is the office to call23. We could not confirm whether the city adds septic rules of its own, so ask the Building Department too.
Septic is rarely the answer here. The county health department states that central sewer is almost universally available in Monroe County and that every location where sewer is available must be connected23. Septic systems that remain in the Florida Keys must be Performance Based Treatment Systems24. Monroe County's soil survey shows 0% of soils rated "not limited" for a conventional drain field, so a conventional field is unlikely25. Well permits inside the city are unconfirmed; the South Florida Water Management District issues well permits for the county26.
Building a home in Key Colony Beach: the steps, in order
- Confirm the lot's district (R-1A, R-1B, R-3, RH or B-1) and its lot size, setbacks and height limits with the Building Department113.
- Order a lot survey from a registered surveyor; one is required before a new building or seawall27.
- Check flood exposure: the city amends the residential flood provisions of the Florida Building Code10.
- Submit the building permit application with 3 complete sets of plans and the legal description with lot, block and subdivision27.
- Use a state- or Monroe County-licensed contractor, or qualify as owner/builder: one new single-family permit in 5 years, the owner on site during work and inspections277.
- Pass every inspection during construction11.
- Ask the Building Department about the certificate of occupancy; we could not confirm the city's closeout steps13.
What to check before you buy in Key Colony Beach
Check the district first: minimum home size, setbacks and height limits differ between R-1A and R-1B98. Elevation matters too, since the 30-foot height cap tightens for living space below base flood elevation20. Monroe County enforces floodplain rules that raise the lowest floor to base flood elevation for structures built after 1974; ask whether the city applies the same standard to your lot28.
Costs run high. Monroe County's typical home value is about $966,00029, the typical home insurance premium about $7,871 a year30, and the effective property tax rate 0.5%31. These figures describe the county, not the city. Land outside the city limits falls under the unincorporated Monroe County rules on the Monroe County page.
Watch-outs
- Monroe County's building, planning and growth-allocation (ROGO) rules cover unincorporated land; we could not confirm how or whether ROGO applies to a lot inside Key Colony Beach, so ask the city Building Department before you rely on a county rule32.
- We could not confirm the city's fee schedule, certificate of occupancy steps or short-term rental rules; ask the Building Department at (305) 289-1212, ext. 313.
- Florida law limits how far a local government can restrict vacation rentals, with an exception for rules adopted on or before June 1, 2011; confirm the city's rule before buying for rental income33.
Sources
- Sec. 101-11. R-1B One dwelling unit residence district (Key Colony Beach), quoted and re-checked
- Sec. 6-6. Building permit (Key Colony Beach), quoted and re-checked
- Sec. 101-55. Commercial and recreational vehicles (Key Colony Beach), quoted and re-checked
- Septic Tanks, quoted and re-checked
- Sec. 11-2. Camping, tenting, sleeping in open (Key Colony Beach), quoted and re-checked
- Sec. 101-104. Manufactured homes and recreational vehicles (Key Colony Beach), quoted and re-checked
- Sec. 6-6. Building permit (Key Colony Beach), quoted and re-checked
- Sec. 101-11. R-1B One dwelling unit residence district (Key Colony Beach), quoted and re-checked
- Sec. 101-10. R-1A One dwelling unit residence district (Key Colony Beach), quoted and re-checked
- Sec. 6-2. Codes adopted (Key Colony Beach), quoted and re-checked
- Sec. 6-6. Building permit (Key Colony Beach), quoted and re-checked
- Building and Permitting, quoted and re-checked
- City of Key Colony Beach Building Department (keycolonybeach.net)
- Right-of-Way Use Permits, quoted and re-checked
- Current Planning, quoted and re-checked
- Sec. 101-11. R-1B One dwelling unit residence district (Key Colony Beach), quoted and re-checked
- Sec. 101-11. R-1B One dwelling unit residence district (Key Colony Beach), quoted and re-checked
- Sec. 101-10. R-1A One dwelling unit residence district (Key Colony Beach), quoted and re-checked
- Sec. 101-10. R-1A One dwelling unit residence district (Key Colony Beach), quoted and re-checked
- Sec. 101-11. R-1B One dwelling unit residence district (Key Colony Beach), quoted and re-checked
- Sec. 101-10. R-1A One dwelling unit residence district (Key Colony Beach), quoted and re-checked
- Florida Statutes § 163.31771: Accessory dwelling units (Florida statewide rule), quoted and re-checked
- Florida Department of Health in Monroe County (monroe.floridahealth.gov)
- Septic Tanks, quoted and re-checked
- 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
- Well Construction Permits, quoted and re-checked
- Sec. 6-6. Building permit (Key Colony Beach), quoted and re-checked
- Building Responsibly & Requirements, quoted and re-checked
- Typical home value (Zillow): Bolthole Index county data
- Typical home insurance premium: Bolthole Index county data
- Effective property tax rate: Bolthole Index county data
- Current Planning, quoted and re-checked
- leg.state.fl.us (Florida statewide rule), quoted and re-checked
Written October 16, 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.