BFE + freeboard isn’t the whole story. Elevation is set by the base flood elevation (BFE) plus local freeboard, but livability and cost hinge on access, stairs/lifts, and how water moves under and around the house. You can be “to code” and still make a daily‑life mistake (too many stairs, driveway that ponds, traps for drift debris).
A practical rule of thumb: Start with FFE = BFE + required freeboard. If the property is flat and access works, consider +6–12 inches for margin. If steep or constrained, stay tight to required elevation and design drainage and ramps early.
What good looks like: Elevated living floor above BFE, utilities and HVAC above design flood level, lower‑level enclosure either fully flood‑compatible (vents, breakaway walls) or kept open, and site grading that drains away from piers and pile caps.
Soil decides more than you think
What the geotech actually tells you: Beyond “good/bad soil,” you’re looking for allowable axial capacity (compression/uplift), lateral resistance, and depth to competent bearing. In coastal sands, uplift and lateral are often the limiters—not compression.
Why that matters for piles: If lateral capacity is low, stiffer/stronger piles or deeper embedment help; with fiberglass pilings, you can achieve capacity through depth and grouping while maintaining corrosion immunity.
The load path principle: Wind loads try to lift the roof, rack the walls, and push laterally. A hurricane‑proof home moves that energy from roof diaphragm to wall panels to foundation elements to soil, without soft spots.
Monolithic shell advantage: With a SCIP shell, the roof slab and walls act together. Tied into fiberglass pilings via engineered pile caps and grade beams, the house behaves like a single piece. That’s the opposite of a framed roof relying on add‑on hardware after the fact.
Practical details to get right: Align pile groups with major shear walls; design grade beams so wall panels bear directly over them; specify corrosion‑resistant connectors above grade; keep penetrations out of high‑moment zones at pile caps.
Choose fiberglass pilings when you’re within salt air or brackish water, you want “build it once” longevity with minimal maintenance, or your design benefits from lighter, easier‑to‑handle elements and fewer steel connections/braces.
Timber can still make sense when budget is extremely tight, exposure is mild, and you accept a shorter service life and more maintenance.
Steel can make sense for high loads and specialized connectors are needed, but even in those cases, fiberglass is comparable (often more industrial than residential).
Concrete can make sense when access allows heavy equipment and you have a plan to protect against chloride intrusion—just watch the long‑term spalling risk. Fiberglass pilings slide in like butter, and are more eco-friendly than concrete.
“To code” but unlivable: Meeting BFE + freeboard, then realizing the driveway is too steep or stairs dominate the facade. Fix: model slopes and steps before you finalize FFE.
Over‑braced timber under salt air: The brace bolts become the failure points. Fix: specify fiberglass pilings and reduce connections where engineering allows.
Utilities too low: Condensers and panels installed below design flood level because “we needed the space.” Fix: plan mechanical platforms early.
No thought for water under the home: Closed skirting in a velocity zone. Fix: use flood vents or breakaway walls where required.
A geotech report summary with design parameters for axial, uplift, and lateral. A pile schedule detailing fiberglass composite material, diameter, spacing, and embedment depth. Pile cap and grade beam details with rebar schedules and connection notes to the superstructure. Elevation certificate targets (BFE, freeboard, FFE) plus mechanical equipment elevations. Flood compliance notes for vents, breakaway details, and lower‑level materials. Corrosion and maintenance notes for any above‑grade metal components.
Upfront: Fiberglass pilings often cost more per stick than timber. But the lighter weight can reduce crane time, fewer braces and connections may be required, and inspections are straightforward. Many projects end up close to cost‑neutral at install.
Long term: The no‑rust/no‑rot reality plus fewer connection points usually means far lower maintenance and replacement risk over 20–40 years. If you plan to keep the property, lifecycle wins beat initial savings.
If you want a foundation and elevation plan that’s quiet, durable, and hurricane‑proof, bring us your survey and flood map. We’ll size the finished floor elevation, specify fiberglass pilings where they make sense, and tie everything into a monolithic SCIP shell so the house works as one.
