House Plan Sealing
Purchased plans engineered for your lot and sealed for South Carolina permit submission — foundation, framing, bracing, and connections.
Learn more →Structural Engineer Licensed in South Carolina
From Charleston's high-wind, high-seismic peninsula to lake lots outside Greenville, South Carolina packs more structural variety into one state than almost anywhere we work. Oakline seals house plans and designs structural systems across the state remotely — engineered to the 2021 code South Carolina actually enforces, and to the coastal wind and seismic realities that make Lowcountry construction its own discipline.
★★★★★ 5.0 on Google · 84 verified reviews · Cody Johnston, PE, MBA · SC License #43080
What We Do in South Carolina
Serving Charleston, Mount Pleasant, Summerville, Hilton Head, Myrtle Beach, Columbia, Greenville, Spartanburg, and Rock Hill. Every project is personally engineered by Cody Johnston, PE, MBA — one engineer, no hand-offs, and drawings your builder can actually build from.
Foundation Design
Footings, slabs, piers, and walls designed from your site conditions — not a generic detail sheet.
Beam & Framing Design
LVL, steel, and engineered-lumber sizing for renovations, wall removals, and "beam by others" notes on your plans.
Learn more →Additions & ADUs
Structural design that ties new construction into your existing home correctly.
Learn more →South Carolina building codes: 2021 editions, statewide
South Carolina enforces the 2021 International Residential Code and 2021 IBC with South Carolina amendments, effective statewide since January 1, 2023. The state Building Codes Council runs a mandatory adoption cycle, so unlike some neighboring states, every SC jurisdiction reviews against the same editions. The 2024 editions are working through the Council's modification-and-adoption process now; until that lands, the 2021 codes govern — and we design to whichever edition your permit office enforces on the day you submit.
The 2021 IRC matters for homeowners because it pulls in newer wind provisions and tightened bracing requirements compared to the older codes many stock plans were drawn to. A plan set drafted for a 2015-code state routinely needs its wall bracing, uplift connections, and header designs rechecked before a South Carolina reviewer will pass it.
Coastal wind — and the seismic zone nobody expects
The coast is the headline: Charleston, Mount Pleasant, Hilton Head, and the Grand Strand sit in design wind speeds where prescriptive framing tables run out fast. Wind-borne debris regions add opening-protection requirements, and elevated foundations near the water bring pile and pier design into play. This is exactly the work Oakline does daily — high-wind lateral design is the core of our practice, not an add-on.
Here's the one that surprises people: the Charleston area is one of the highest seismic design regions on the East Coast, a legacy of the 1886 earthquake. Homes in much of the Lowcountry are designed for earthquake loads that rival parts of California — which changes shear wall layouts, hold-downs, and foundation detailing. A stock plan from a catalog has never heard of this. Your engineer has to.
Upstate — Greenville, Spartanburg, Rock Hill — the wind and seismic demands ease, but sloped lots, walkout basements, and fast-growing subdivisions keep engineered foundations and retaining conditions in the picture.
How Remote Engineering Works
- 1.
Send your plans. Upload your plan set through our site — any size, straight to our secure project drive. Cody reviews them personally, for free, and comes back with straight advice and a firm price, usually within a day or two.
- 2.
We engineer to the South Carolina code. Foundation, framing, bracing, and connections designed for your specific lot — with the governing code edition noted right on the drawings so your reviewer sees it immediately.
- 3.
You get sealed drawings. Digitally sealed PDFs under South Carolina PE license #43080, ready for permit submission — and Cody stays available to answer reviewer or builder questions after delivery. Most plan sealing projects finish within 2 weeks.
Verify the License
Cody Johnston is a licensed Professional Engineer in South Carolina — license #43080, issued by the South Carolina Board of Registration for Professional Engineers and Surveyors. Don't take our word for it: verify it with the state board →
Also licensed in six additional states — see all license states.
South Carolina Questions, Answered
Is South Carolina on the 2021 or 2024 codes right now?
The 2021 IRC and IBC with South Carolina amendments, statewide since January 2023. The 2024 editions are in the state adoption process; we track it and design to whichever edition your jurisdiction enforces at permit time.
Why does my Charleston-area project need seismic design?
The Charleston region carries some of the highest seismic design values on the East Coast from the 1886 earthquake zone. Building codes require homes there to be designed for earthquake loads in addition to hurricane wind — it affects bracing, hold-downs, and foundations.
Can you seal plans for a beach house on the SC coast?
Yes. High-wind design, wind-borne debris provisions, and elevated pile or pier foundations are our regular work. We design remotely and deliver sealed drawings your local permit office accepts.
Building in South Carolina?
Cody personally reviews your plans — flagging structural issues, finding ways to save on your build, and giving straight advice for the right foundation and framing choices specific for your lot. Free, no obligation, and he can also give you a firm engineering price in a day or two.
Have an Engineer Review My Plans — Free