Can you live off-grid in St. Johns County, Florida?
84
of 100
Good with caveats
Yes, with two things to plan around. Rain is plentiful, about 53 inches a year. The U.S. Forest Service rates wildfire risk high across much of the county, so plan cleared ground around the house. NOAA counts three hurricane-strength storms within 50 miles since 1975, so build to the wind code and plan for long outages.
What the land says
Rain
Rain can supply much of a household's water with a large tank. The sandy soil dries fast, so plan to water the garden.
About 53 inches a year (PRISM, 1991 to 2020 average)
Wells
Typical well depth. Budget for a mid-range well.
The typical well here is about 290 feet deep; a well typically runs $11,000 to $23,000
Growing season
Long enough for a spring and a fall garden.
About 320 frost-free days, USDA zone 9b; last frost about February 8, first about December 15
Sun
Good sun. Size the array and battery bank for winter.
About 5.4 hours of full sun a day, averaged over the year
Flood
Flood zones run along creeks and rivers here. Look up the parcel on FEMA's flood map.
FEMA maps flood zones in places
Wildfire
Wildfire risk is high across much of the county. Plan cleared ground around the house and fire-resistant materials.
U.S. Forest Service wildfire hazard map: Moderate to High here
Storms
Expect about two hurricanes within 50 miles over 30 years. Build to the wind code and keep a week of fuel and water.
NOAA: three hurricane-strength storms within 50 miles since 1975; about 1 strong (EF2 or stronger) tornado a decade within 25 miles
Terrain
Flat, but the ground stays wet. Build on the higher, drier spot.
Slopes average about 1%, about 30 feet above sea level
Soil
Expect a costlier septic system, because the soil stays wet for long stretches. The county's soil test decides.
Sand, poorly drained (USDA soil survey). A mound, sand filter, or treatment unit typically runs $10,000 to $20,000
Road
Paved roads are close by.
Nearest paved road usually within about 0.8 miles (OpenStreetMap)
Check a Florida parcel, or plan the one you own
Get a free 0-100 off-grid score.
A step-by-step build plan, sizing your solar, water, garden, septic, heat, and buildings.
Is it legal here?
Zoning
St. Johns County zones land outside its towns and publishes its zoning map. Our free lookup shows the district for any address.
Building code
Florida Building Code mandatory statewide, updated on a 3-year cycle. Local amendments cannot reduce standards.
Rainwater
Collecting it is allowed.
Composting toilets
Allowed with a permit and an approved unit.
Water rights
Owners of land along a creek or lake can make reasonable use of its water.
Drilled to about 290 feet, with pump and pressure tank
Septic
$10,000 to $20,000
Mound, sand filter, or treatment unit
Solar and batteries
$17,000 to $36,000
Sized for a modest household
Road or driveway
$3,000 to $7,000
From the nearest road to a house site
Clearing
$1,000 to $3,000
A house site, solar, and garden
Total
$40,000 to $90,000
Before the house
Before you make an offer on land here
Soil test
Get a soil test before you count on septic.
The soil stays wet, which can rule out a standard system.
Flood map
Look up the parcel on FEMA's flood map.
Flood zones run along creeks and rivers here. Building in one means flood insurance and extra permits.
Wildfire
Ask an insurance agent whether they will write a policy.
The U.S. Forest Service rates wildfire risk high across much of the county.
Nearby counties
320,110 people live in St. Johns County, about 532.9 per square mile. It ranks tied for 30th of the 67 Florida counties we scored, and Florida ranks 33rd of 50 states.