Ground-Level Enclosure Plans for Elevated Homes in Florida

Homeowners, builders and lift contractors with a house that has been raised on a new foundation, usually after Helene, Milton or Ian, and an open space underneath. The lift is done or on its way. What is left is the ground level: a storage room, a garage bay, a covered entry with stairs, a slab, walls or screening around the pilings. In many communities that is its own permit, separate from the lift, and it has to be drawn to the flood rules for the zone the lot sits in.

What is in the set

• Enclosure plan and elevations with wall layout, door locations and the flood-vent schedule (count, size, position).
• Wall framing for the zone: solid walls with vents where the code allows them, or screening, lattice or breakaway walls where it does not.
• Breakaway wall framing and connections, drawn to give way in a flood without pulling on the lifted house or its foundation.
• Stairs and any entry door at the top of the stairs, with the details the flood zone calls for.
• Slab-on-grade, drawn not to be tied to the foundation where the zone requires that.
• Material notes for everything below the flood line, utilities kept off breakaway walls, and a use note on the sheet: parking, building access or storage only.
• Sealed, digitally signed PDF sheets named for the building department.

The flood-zone logic, in plain words

• What the space can be used for. Below the required elevation, an enclosed area is for parking, building access or storage. That is the Florida Building Code, Residential, 8th Edition (2023), section R322. Not a bedroom, not a finished room. Air handlers, water heaters, plumbing fixtures and finished drywall do not belong there.
• What "required elevation" means. In the 8th Edition the rules apply below the required elevation, which is the base flood elevation plus one foot, or the design flood elevation if your community sets a higher one. The survey and Elevation Certificate tell us which.
• Inland flood zones (A and AE). Solid walls are allowed if they have flood vents. The rule: at least 1 square inch of net opening for every square foot of enclosed floor area, measured on the outside of the walls; at least two openings, on different sides; the bottom of each within 1 foot of the ground or the floor; each at least 3 inches across. A door or window counts only if vents are installed in it.
• Coastal A and V zones. Walls under the house have to be insect screening, open lattice, or breakaway walls, and breakaway walls need flood vents too. Breakaway means built to give way at a set load, between 10 and 20 pounds per square foot under the code, so the walls let go before the flood damages the house above. Where the code's wind load is higher than that, the code asks for the sealed design documentation we put on the sheets. If the stairs are enclosed, the code asks for a door at the top.
• Materials. Floors and walls below the required elevation use flood damage-resistant materials (FEMA Technical Bulletin 2).
• Insurance and local rules. The National Flood Insurance Program does not cap enclosure size, but a solid enclosure can raise the flood insurance rate, more so in V zones and at 300 square feet and up. Some communities set their own limits or require a non-conversion agreement recorded on the deed. We check both by parcel before drawing, and your insurance agent should hear about the plan early.

What we need from you

The survey showing the flood zone and design flood elevation; the Elevation Certificate; the lift plans (we draw to the foundation your lift contractor designed, we do not redesign it); and photos of the underside of the house, the ground and the stairs.

What stays with others

The lift itself stays with your lift contractor and their engineer. Substantial-damage determinations are your building department's. The set picks up at the new foundation and covers the ground level. Everything is remote, from your documents and photos; your contractor confirms field dimensions. Building new instead of lifting? See a new beach house on pilings or house plans with an elevator.

Where we work

Elevated-home work runs across the four areas below. Pick yours:

• Space Coast: Melbourne, Palm Bay, Merritt Island, Cocoa Beach, Satellite Beach, Melbourne Beach
• Treasure Coast: Port St. Lucie, Jensen Beach, Palm City, Hobe Sound, Vero Beach, Stuart
• Pinellas beaches and bayside: St. Pete Beach, Treasure Island, Madeira Beach, Indian Rocks Beach, Dunedin, Gulfport, St. Petersburg, Clearwater
• Palm Beach: Palm Beach, North Palm Beach, Tequesta, Jupiter, Palm Beach Gardens, Boca Raton, Delray Beach, Wellington

Questions

Can I enclose under my elevated house?

Yes, for parking, building access and storage. The Florida Building Code limits the space below the required elevation to those uses and asks for flood vents or breakaway walls, depending on the flood zone. It cannot be a bedroom or finished living space. Local rules can add limits, so we check your community before drawing.

How big can a storage enclosure under a raised house be?

The building code has no single size cap for the enclosure, and FEMA does not limit size either. But insurance rates climb with enclosures, especially in V zones at 300 square feet and up, and some communities set their own limits. That is why we check your parcel's rules and ask for your flood zone before we draw.

What are flood vents and how many do I need?

Flood vents are openings that let floodwater flow in and out so the walls are not pushed over. The code asks for 1 square inch of net opening per square foot of enclosure, at least two openings on different sides, each bottom within 1 foot of the ground or floor. We put the count and positions on the sheet.

What is a breakaway wall?

A breakaway wall is a non-structural wall under a lifted house, in a V zone or Coastal A zone, built to fail in a flood without damaging the house or its foundation. The code sets its strength between 10 and 20 pounds per square foot, or a sealed design where wind loads are higher. Breakaway walls also need flood vents. Utilities cannot run through them.

Will an enclosure raise my flood insurance?

It can. Without compliant vents, the enclosure floor can be rated as your lowest floor, and in V zones any enclosure is rated higher, more at 300 square feet and up. Open lattice or screening keeps the best rate. Ask your insurance agent before choosing solid walls, and send us what they say.