TL;DR: New homes in Horry County's mapped flood zones must be elevated above the base flood level — 3 feet (36 inches) in AE and VE zones, and 24 inches above grade in Zone A without a set base flood elevation. A finished-construction elevation certificate proves the home meets those rules before it can pass final inspection.
Building near the coast means building around water. Along the Grand Strand, foundation height is not a design preference — it is code. According to CCAR MLS (2026), the median sales price across the local market held near $324,473 over the trailing 12 months, and a large share of that inventory sits inside FEMA-mapped flood zones. For anyone planning new construction in Myrtle Beach or the wider Horry County area, the rules governing how high a home must sit are among the most important — and most misunderstood — parts of the process. Here is what the county actually requires, zone by zone.
Horry County Flood Zone New Construction Requirements
Every new build starts with a permit. According to Horry County SC.Gov (2026), a permit is required in the unincorporated areas of the county whenever construction or improvement to a building costs more than $500 in materials and labor. That low threshold means nearly every project needs county sign-off before work begins.
Flood rules layer on top of that. The county enforces elevation standards inside three mapped flood zones: AE, VE, and A. These are the "special flood hazard areas" where FEMA expects a base flood — a flood with a 1% annual chance — to reach a defined water level called the base flood elevation (BFE).
Required foundation height depends on which zone a lot falls in. That is why two homes on the same street can sit at very different heights. A parcel mapped in a high-risk AE or VE zone carries a strict elevation mandate. A lot outside those mapped zones does not carry the same 3-foot rule — which is often why buyers notice some coastal homes sitting closer to grade. Confirming a lot's flood zone is step one, before design and before budget. Smart lot selection accounts for elevation, drainage, and soil from the very start.
Foundation Elevation Rules by Flood Zone
Horry County builds above the federal floor. Where the National Flood Insurance Program (NFIP) sets a baseline at the base flood elevation, the county adds "freeboard" — extra height for a margin of safety.
According to Horry County SC.Gov (2026), the requirements break down this way:
AE zones: The lowest floor must sit at least 3 feet (36 inches) above the base flood elevation.
VE zones: The bottom of the lowest horizontal structural member must sit at least 3 feet (36 inches) above the base flood elevation. VE zones face wave action, so the standard measures the support beams, not the floor.
Zone A without an established BFE: The lowest floor must sit at least 24 inches above the highest adjacent grade.
Mobile homes placed in a flood zone carry one extra rule: the platform for the air-conditioning condenser must be built above the base flood level, or the inspection fails, per Horry County SC.Gov (2026). You can see how foundation elevation ties into insurance incentives in our related guide.
Table: Horry County Elevation Requirements by Flood Zone
| Flood Zone | Elevation Requirement | How Height Is Verified |
|---|---|---|
| AE | Lowest floor ≥ 3 ft (36 in) above base flood elevation | Finished-construction elevation certificate |
| VE | Bottom of lowest horizontal structural member ≥ 3 ft (36 in) above base flood elevation | Finished-construction elevation certificate |
| A (no established BFE) | Lowest floor ≥ 24 in above highest adjacent grade | Building inspector; certificate by owner or licensed surveyor/engineer |
Source: Horry County SC.Gov, Build Responsibly (2026).
The Elevation Certificate: Proving Compliance
Meeting the height rule is only half the job. You also have to prove it. Horry County requires a finished-construction elevation certificate to verify that a completed home sits at the correct height, according to Horry County SC.Gov (2026).
The elevation certificate is a FEMA form completed by a licensed land surveyor, engineer, or architect, who measures the as-built structure and certifies the numbers. The form records the top of the lowest floor, the next higher floor, the lowest machinery or equipment, and both the lowest and highest adjacent grade. In V zones, it also records the bottom of the lowest horizontal support member.
One practical note that trips up first-time builders: a certificate based only on construction drawings is not final. A new certificate is required once the building is complete. Plan for that post-construction survey inside your project schedule so it does not stall your closeout — it fits alongside the county's other building permit and inspection milestones.
The 50% Rule for Renovations and Rebuilds
Flood rules do not stop at brand-new homes. According to Horry County SC.Gov (2026), the NFIP applies a "substantial improvement" standard: if the cost of reconstruction, additions, or other improvements equals or exceeds 50% of the building's market value, the structure must meet the same construction requirements as a new building.
The same math applies to damage. A home damaged so that repairs equal or exceed 50% of its pre-damage value must be elevated above the base flood elevation, just like new construction, per Horry County SC.Gov (2026).
For owners of older, lower-set homes across the Myrtle Beach and Horry County area, this rule carries real weight. A major remodel can trigger full elevation compliance — which reshapes the scope, cost, and timeline of a project. Because this is a regulatory matter, confirm the numbers early with Horry County Code Enforcement (843-915-5090) and consult a licensed professional for your specific situation before finalizing plans.
Flood-zone rules shape a new home's height, cost, and inspection path long before the first slab is poured. If you are weighing a lot in the Grand Strand and want to understand how its flood zone affects foundation design and your build timeline, our team can walk you through it. Reach out to start the conversation about building responsibly in Horry County.
FAQ SECTION
Which flood zones require elevated foundations in Horry County?
Horry County enforces elevation standards in three mapped special flood hazard areas: AE, VE, and A, according to Horry County SC.Gov (2026). In AE and VE zones, new homes must be raised at least 3 feet (36 inches) above the base flood elevation. In Zone A without an established base flood elevation, the lowest floor must sit at least 24 inches above the highest adjacent grade. Lots outside these mapped zones do not carry the same elevation mandate, which is why required heights vary from parcel to parcel across the Grand Strand.
How high must a new home sit in an AE flood zone in Horry County?
In an AE zone, the lowest floor must be elevated at least 3 feet — 36 inches — above the base flood elevation, per Horry County SC.Gov (2026). This is stricter than the federal minimum because the county adds "freeboard," an extra safety margin above the base flood level. The finished height is confirmed with a finished-construction elevation certificate completed by a licensed surveyor, engineer, or architect once the home is built. That certificate is required before the home can clear final inspection.
Why do some Myrtle Beach homes sit at ground level in flood-prone areas?
Required foundation height depends on a lot's mapped flood zone. Horry County SC.Gov (2026) applies elevation rules specifically to AE, VE, and A zones. A parcel mapped inside one of those high-risk zones must be raised 3 feet above the base flood elevation (or 24 inches above grade in Zone A). A lot that falls outside those mapped high-risk zones does not carry the same 3-foot rule, so a home there can legally sit closer to grade. Always confirm a lot's zone before assuming its required height.
Do I need an elevation certificate for new construction in a flood zone?
Yes. Horry County requires a finished-construction elevation certificate to verify that a completed home meets the correct height in AE and VE zones, according to Horry County SC.Gov (2026). A licensed surveyor, engineer, or architect measures the as-built structure and certifies the numbers. In Zone A without a base flood elevation, the building inspector verifies height, and the certificate is completed by the owner or a licensed surveyor or engineer. A certificate based on drawings alone is not final — a new one is required once construction is complete.
What is the 50% "substantial improvement" rule?
Under the NFIP standard relayed by Horry County SC.Gov (2026), if reconstruction, additions, or other improvements to a building equal or exceed 50% of its market value, the structure must meet the same construction requirements as a new building. The same applies to damage: a home damaged so repairs reach or exceed 50% of its pre-damage value must be elevated above the base flood elevation. A large remodel of an older, lower-set home can trigger full elevation compliance, so check the math early.
When is a building permit required in unincorporated Horry County?
A permit is required in the unincorporated areas of the county whenever construction or improvement to a building costs more than $500 in materials and labor, according to Horry County SC.Gov (2026). That low threshold means nearly every meaningful project needs county review. In flood zones, permitting also brings the elevation and elevation-certificate requirements into play, so it is wise to confirm a lot's flood zone before you finalize design or budget.
Sources
Horry County Government (Build Responsibly): https://www.horrycountysc.gov/departments/emergency-management/flooding/build-responsibly/
Coastal Carolinas Association of REALTORS® (CCAR MLS Market Stats): https://www.ccarsc.org/pages/marketstats/
Flood Zones, Foundation Elevation & Insurance Incentives in Myrtle Beach for 2026
Understanding Risk Rating 2.0 for Myrtle Beach Builders (2026)
