A whole home renovation in Myrtle Beach is shaped by two regulatory questions before anybody picks a floor plan or a countertop: is the address in a mapped flood hazard area, and will the cost of the work reach 50 percent of the market value of the structure?
A whole home renovation in Myrtle Beach is shaped by two regulatory questions before anybody picks a floor plan or a countertop: is the address in a mapped flood hazard area, and will the cost of the work reach 50 percent of the market value of the structure? Under the federal definition at 44 CFR 59.1, crossing that 50 percent line makes the project a substantial improvement, which means the building has to meet the requirements that apply to new construction, and in a flood hazard area those requirements can include elevating the structure. Every other decision in a full remodel gets easier to judge once those two answers are in hand.
Top GM Construction is a licensed and insured general contractor with more than 17 years of experience, handling whole home renovation work in Myrtle Beach, North Myrtle Beach, Conway, Surfside Beach, Murrells Inlet and Little River, South Carolina. What follows is what the code, the state statute and Horry County actually publish, with the source named each time, so you can hold any proposal you receive (ours included) to the same standard.
Renovating does not force the whole house up to current code, with one large exception
A whole home renovation does not, as a general rule, force the entire existing house up to today’s code, which is the most common fear at the start of a full remodel. Section R102.7.1 of the South Carolina Residential Code (2021) provides that additions, alterations and repairs conform to the requirements for a new structure without requiring the existing structure to comply with the code, unless the code says otherwise, and that the work cannot make the existing building less conforming than it was before. New work meets new standards. The parts you do not touch are generally left alone, and you are not allowed to make anything worse. The one large exception is a flood hazard area, where a project determined to be a substantial improvement under 44 CFR 59.1 does have to meet the requirements that apply to new construction.
One sourcing caution, which applies to every code section cited below: the code text here comes from a code reproduction service rather than from the adopting authority, so confirm the current wording and how your jurisdiction applies it with your local building official before you rely on it.
The South Carolina Residential Code (2021) also defines two words that get used loosely in proposals. In its chapter 2 definitions, an alteration is any construction, retrofit or renovation to an existing structure other than a repair or an addition that requires a permit, and an addition is an extension or increase in floor area, number of stories or height. That distinction matters for scope and for budget, because a project that includes new square footage is partly a home addition and gets reviewed as one.
Which code edition your renovation is judged against
South Carolina has been building under the 2021 code editions since January 1, 2023, the implementation date the South Carolina Building Codes Council set for local jurisdictions when it adopted those editions on October 6, 2021, "to be enforced by all municipalities and counties in South Carolina." A 2024 cycle is in process on the Council’s own adoption page, with no effective date announced as of this writing, so check llr.sc.gov/bcc rather than taking a date from a blog, including this one.
Two code details worth knowing before you shop materials. First, the mandatory energy code in South Carolina is the 2009 International Energy Conservation Code, adopted under the Energy Standard Act and listed that way in the Building Codes Council’s own 2021 adoption notice, not the 2021 edition. Insulation, air sealing and window replacement are judged against that standard, which is older than the edition a manufacturer catalog is likely to cite.
Second, the Council’s adoption notice lists the 2021 International Existing Building Code among the adopted codes, while the state statute at S.C. Code 6-9-50 names a shorter mandatory list and 6-9-60 places existing building codes among those a municipality or county may adopt by ordinance. Those two sources do not line up, and we are not going to resolve the conflict here. For a single family house, the practical answer is that the renovation is handled under the residential code, and whether the existing building code also applies is a question for your building official.
The 50 percent rule, in the words of the regulation
The 50 percent rule comes from the National Flood Insurance Program, not from the building code chapter your contractor is quoting from, and it is the rule that reorders a whole home renovation budget. Under 44 CFR 59.1, a substantial improvement is:
"Any reconstruction, rehabilitation, addition, or other improvement of a structure, the cost of which equals or exceeds 50 percent of the market value of the structure before the ‘start of construction’ of the improvement."
Read the two halves of that fraction carefully, because people get both wrong. In the 44 CFR 59.1 definition, the numerator is the cost of the improvement and the denominator is the market value of the structure, not the property. Land value is not in it, and on the Grand Strand the land often carries a large share of what the address is worth, which makes the structure value smaller than homeowners assume and the 50 percent line closer than they expect.
44 CFR 59.1 defines substantial damage on the same 50 percent threshold: damage of any origin where the cost of restoring the structure to its before damaged condition would equal or exceed 50 percent of the market value of the structure before the damage occurred. If a storm or a water loss put you into this project, the determination may already be on the table.
Three more pieces of the 44 CFR 59.1 definition that affect planning:
- Start of construction is the date the building permit was issued, provided the actual work begins within 180 days of that date. The permit date is the clock, not the day the dumpster arrives.
- Correcting an existing violation of a state or local health, sanitary or safety code identified by a local authority, limited to the minimum necessary for safe living conditions, is excluded from the calculation.
- Alterations to a structure listed as historic are excluded when the alteration preserves the historic designation.
The local floodplain authority runs the number and issues the substantial improvement verdict, not the contractor and not the homeowner. How a given jurisdiction establishes the market value of a structure (tax assessment, an appraisal, a replacement cost table) is a local procedure, and we are not going to publish a method we did not verify for Horry County or for the City of Myrtle Beach. Ask the floodplain administrator directly, early, before the scope is locked.
When the determination lands on the substantial improvement side, the residential code closes the circuit. Section R322.1 of the South Carolina Residential Code (2021) directs that buildings in flood hazard areas, including substantial improvement and repair of substantial damage, be designed and built to the flood resistant construction provisions, and that a building sitting in more than one flood zone follow the more restrictive one. Our source for that section is a code reproduction that we could not read in full, so we are describing it rather than quoting it, and the wording that governs your project is the wording your building official enforces.
Myrtle Beach holds a standard above the federal minimum
The federal definition at 44 CFR 59.1 is a floor that a community may build above, not a ceiling. In a case study published by FEMA, last updated February 11, 2021, the City of Myrtle Beach is described as going past the federal minimum in three ways:
- New construction "must be elevated at least three feet above the Base Flood Elevation (BFE)."
- The city monitors substantial improvement cumulatively, "limiting improvements to a total of 50% over a 10 year period."
- The city designated a Coastal Protection Zone where new buildings cannot be erected.
That required margin above the base flood elevation, which is the flood level FEMA’s maps give for a location, is what floodplain programs call freeboard.
The cumulative part is the one that catches people. Under a strict reading of the federal definition, a single project is measured on its own. Under a cumulative standard, the improvements add up across a window of years. A kitchen project one year, a bathroom project the next, and a larger phase after that can total past the line without any single phase looking close to it. If you are planning a full remodel in stages to spread the spending, ask the city how prior permits on your address will be counted before you commit to the sequence. That question costs nothing early and can cost an elevation later.
Two cautions on that FEMA document. It is dated, and community flood program standings get reassessed, so we are not publishing the community rating or the insurance discount figure it contains as if they were current. And the city’s own permit requirements could not be verified in a primary source for this article. So we are naming only what Horry County publishes, and telling you to confirm anything city specific with the building department for your city.
What Horry County requires, and where to look up your flood zone
Horry County states the same 50 percent rule in its own words on its Build Responsibly page: "if the cost of reconstruction, additions, or other improvements to a building equals or exceeds 50% of the building’s market value, then the building must meet the same construction requirements as a new building." The county requires an elevation certificate, the document that records how high the lowest floor sits, in AE and VE zones to verify that the lowest floor is located not less than 3 feet (36 inches) above the level of the base flood. In a Zone A where no base flood elevation has been established, the county says the elevation certificate has to be prepared by the owner or by a licensed surveyor or engineer.
To find the flood zone and base flood elevation for a specific address, the official source is the FEMA Flood Map Service Center at msc.fema.gov. FEMA also publishes the technical reference that floodplain administrators use for these determinations, FEMA P-758, the Substantial Improvement and Substantial Damage Desk Reference, if you want to read the same manual the reviewer is reading.
What needs a permit in a whole home renovation
Short answer: effectively all of a whole home renovation needs a permit. Section R105.1 of the South Carolina Residential Code (2021) requires a permit before any owner or authorized agent constructs, enlarges, alters, repairs, moves, demolishes or changes the occupancy of a building or structure. Section R105.2 then lists the work that is exempt, and the list is narrow: one story accessory structures up to 200 square feet, fences not over 7 feet, retaining walls up to 4 feet, sidewalks and driveways, finish work, small detached decks no more than 200 square feet and no more than 30 inches above grade, plus minor electrical, gas, mechanical and plumbing repairs.
Look at what is not on that list: reconfiguring a floor plan, removing or modifying a structural wall, replacing systems, moving plumbing, adding circuits, changing openings. That list is the definition of a whole home renovation. A kitchen remodel that relocates a sink and adds circuits is permitted work, and so is a bathroom remodel that moves a drain. Finish work alone is the exception, and nobody gut renovates a house in finish work.
Horry County repeats the R105.1 language on its own code enforcement page for the unincorporated areas of the county, and publishes a local exempt list that includes painting, papering, tiling, carpeting, cabinets and counter tops, replacing floor covering as long as structural sheathing is not replaced, fences not over 7 feet, and the same small low deck. The county also publishes a cost trigger: a permit is required in the unincorporated areas of the county when construction or improvement to any building is at a cost in excess of five hundred dollars. That is a regulatory threshold, not a price for anything.
The jurisdiction question is not academic in this area. Inside city limits, your city issues the permit under its own rules and its own thresholds. In the unincorporated county, Horry County Code Enforcement does. Two houses ten minutes apart can answer to different departments, different local amendments and different submittal lists. Ask in writing which jurisdiction is issuing the permit for your address and who is pulling it.
Which inspections the renovation has to pass
Plan for inspections as well, because they set the rhythm of the schedule more than the crew size does. Section R109 of the South Carolina Residential Code (2021) lists the inspections the code requires: foundation, plumbing, mechanical, gas and electrical rough inspections, floodplain inspections in flood hazard areas, frame and masonry, fire resistance rated construction, and the final inspection. Work that has to be seen cannot be covered before it is seen. Anyone promising to close walls before a rough inspection is describing a problem, not a shortcut.
Who can legally do the work, and a check that takes 30 seconds
South Carolina defines by statute who may take on this work. S.C. Code 40-59-20(6) defines a residential builder as one who constructs, superintends, or offers to construct or superintend the construction, repair, improvement or reimprovement of a residential building not over three floors in height and with no more than sixteen units in any single apartment building, when the cost of the undertaking exceeds five thousand dollars. S.C. Code 40-59-20(7) defines a residential specialty contractor as an independent contractor performing work requiring special skill when the undertakings exceed five hundred dollars and are not regulated under Chapter 11. Both of those figures are legal thresholds, not estimates of what anything costs.
S.C. Code 40-59-30(A) makes it a misdemeanor to act as a residential builder or specialty contractor without the required license or registration, with fines and possible jail time on conviction. The statute also carries an owner exemption at S.C. Code 40-59-260 for a property owner building or improving a residence for personal occupancy rather than for sale or rent, with a recorded statement. If you were planning to act as your own general contractor on a full remodel, read that section carefully, including the part about what you are taking on.
Now the useful part: you can verify a residential builder license yourself through the South Carolina LLR public license lookup at verify.llronline.com, without taking anyone’s word for it. Ask for the business name exactly as it is licensed, then run it. It takes less than a minute, and it is one of the most useful checks you can run before you sign. Our post on why hiring a licensed general contractor matters covers what else to look at once the license checks out.
If the house was built before 1978, the firm has to be lead safe certified
A house built before 1978 changes who is allowed to open its walls. The EPA Renovation, Repair and Painting rule states that, in general, anyone who is paid to perform work that disturbs paint in housing and child occupied facilities built before 1978 must be certified. The rule carries a minor repair exemption for work that disturbs six square feet or less of paint per room inside, or 20 square feet or less on the exterior.
A whole home renovation is not a minor repair. Demolition across multiple rooms blows past six square feet per room on the first day, so the exemption does not apply and the firm doing the work needs to be a lead safe certified firm, meaning one the EPA has certified under that rule. The EPA publishes a public search of certified firms, so this is a second verification you can do on your own in about the same 30 seconds as the license lookup. Ask for the certification before demolition is scheduled, not after.
Wind: who decides the number for your address
Your local building official sets the wind design number for your address. The South Carolina Residential Code (2021) defines hurricane prone regions to include the US Atlantic Ocean and Gulf of Mexico coasts above a stated ultimate design wind speed threshold, which puts this coastline inside that category by definition. What the code does not do is hand you a number for your lot, and we are not going to publish one either.
South Carolina amended the code on exactly this point. The state modification to R301.2.1, codified at S.C. Code Regs. 8-1202 with an update effective May 27, 2022, provides that "the local building official may delineate the wind design category within their jurisdiction provided that it does not surpass those provided on the Applied Technology Council (ATC) website." So the authority over the wind criteria for your address is the building official, bounded by ATC. Not a product brochure, not a salesperson, not an article.
The South Carolina Residential Code (2021) also sets a limit on its own prescriptive path: where wind design is required, or in a special wind region above a threshold the code states, the prescriptive provisions no longer apply and the design has to follow an approved standard instead. Practically, that means "hurricane rated" said out loud is not a specification. The specification is the wind design category your building official assigns and the documented product performance that meets it, in writing, in the scope.
Cost and timeline: what moves them, and why there is no number here
This article does not give you a price range for a whole home renovation in Myrtle Beach, and does not give you a number of weeks. That is deliberate.
The per square foot ranges circulating for this market trace back to contractor marketing pages with no methodology, no sample and no year attached. The national figures that get quoted alongside the phrase "whole home renovation" are averages across every home improvement a household might make, appliance swaps and paint jobs included, which makes them misleading next to a gut renovation. Publishing either one would be inventing precision we cannot source. Our siding guide declined to publish a lifespan in years for the same reason, and our deck guide declined to publish a schedule. The number that applies to your house comes from a written estimate for your address and your scope.
What we can tell you, with the sources above, is exactly what moves both the price and the calendar:
- Scope. Whether new square footage is involved, whether structural walls move, and whether plumbing, electrical and mechanical systems are replaced or extended.
- What demolition finds. Rot, failed framing, water damage, old wiring, old supply lines. The honest version of this is a written procedure for how discoveries are priced, not a promise that there will not be any.
- The permit cycle in your jurisdiction. City or unincorporated county, each with its own review queue and submittal requirements.
- The inspection sequence in Section R109. Foundation, rough systems, framing, floodplain inspections in a flood hazard area, and final. Each one is a gate, and gates are not parallel.
- A substantial improvement determination in a flood zone. This is the one that can change the project rather than delay it, because compliance with new construction requirements can include elevation and an elevation certificate.
Top GM Construction’s published process runs through six stages: Initial Consultation, Detailed Estimate, Contract Signing, Pre-Construction Meeting, Execution and Final Walkthrough. The order is the part that protects you, because the Detailed Estimate comes before the Contract Signing, which is when the questions in the next section should be answered. The same order holds whether the project is a full remodel or one of several remodeling services happening at once.
What to ask for in writing before you sign
Each item below ties back to a source in this article, and each one is answerable on paper. A contractor who is being straight with you will not mind the list.
- The flood zone and base flood elevation for the address, and who looked them up.
- Whether the scope was measured against the 50 percent substantial improvement test, by whom, and whether the jurisdiction counts prior permits cumulatively. Ask the floodplain administrator this one directly.
- Which jurisdiction issues the permit and who pulls it, named, with the application date.
- The state residential builder license, under the exact business name, so you can run it yourself through the LLR lookup.
- Lead safe firm certification, if the house was built before 1978, produced before demolition is scheduled.
- The wind design category assigned by the building official for your address, and the product documentation that meets it.
- The inspection schedule under Section R109, and what gets closed up after each inspection.
- The written procedure for conditions discovered at demolition, including how a change in price and schedule gets approved.
Frequently asked questions
Will a whole home renovation force my entire house up to current code?
Generally no. Section R102.7.1 of the South Carolina Residential Code (2021) provides that additions, alterations and repairs meet the requirements for a new structure without requiring the existing structure to comply with the code, and that the work cannot leave the building less conforming than it was. The large exception is a flood hazard area: if the project is determined to be a substantial improvement under 44 CFR 59.1, the building has to meet the requirements that apply to new construction. Our source for the code section is a code reproduction service, so confirm the wording with your local building official.
How do I find out whether my house is in a flood zone?
Use the FEMA Flood Map Service Center at msc.fema.gov, which is the official source for the flood zone and base flood elevation at a specific address. Horry County also requires an elevation certificate in AE and VE zones, and states that in a Zone A with no established base flood elevation the certificate has to be prepared by the owner or by a licensed surveyor or engineer. Your local floodplain administrator is the authority on how the maps apply to your property.
What is the 50 percent rule, and what happens if my project crosses it?
Under 44 CFR 59.1, a substantial improvement is any reconstruction, rehabilitation, addition or other improvement whose cost equals or exceeds 50 percent of the market value of the structure before the start of construction. The denominator is the structure, not the land. If the local floodplain authority determines that your project crosses the line, the building has to meet the same construction requirements as a new building, which in a flood hazard area can include elevation. Horry County states the same rule in its own words on its Build Responsibly page.
Does Myrtle Beach apply the 50 percent rule more strictly than the federal minimum?
According to a FEMA case study last updated February 11, 2021, yes in three ways: the city requires new construction to be elevated at least three feet above the base flood elevation, it monitors improvements cumulatively, limiting them to a total of 50 percent over a 10 year period, and it designated a Coastal Protection Zone where new buildings cannot be erected. The practical consequence is that two smaller renovations in sequence can add up to a substantial improvement. The document is several years old, so confirm the current standard with the city before planning a phased project.
Does a whole home renovation need a permit in the Myrtle Beach area?
Plan on it. Section R105.1 of the South Carolina Residential Code (2021) requires a permit to construct, enlarge, alter, repair, move, demolish or change the occupancy of a building, and the exempt list in Section R105.2 covers small accessory structures, short fences and retaining walls, sidewalks and driveways, finish work and small low decks. Nothing that defines a full remodel, including floor plan changes, structural walls and system replacement, is on that list. Horry County publishes the same requirement for the unincorporated areas of the county, with a permit required above a cost of five hundred dollars; inside city limits, confirm with your city building department.
My house was built before 1978. Does that change who can do the work?
Yes. The EPA Renovation, Repair and Painting rule states that anyone paid to perform work disturbing paint in housing built before 1978 must generally be certified, and the minor repair exemption only covers work disturbing six square feet or less of paint per room inside or 20 square feet or less outside. A full remodel is far past that, so the firm needs lead safe certification. The EPA publishes a public search of certified firms so you can verify it yourself.
Sources:44 CFR 59.1 (NFIP definitions); FEMA, "Higher Standards Mean Lower Flood Insurance Rates for Myrtle Beach Property Owners" (updated February 11, 2021); FEMA P-758, Substantial Improvement and Substantial Damage Desk Reference; FEMA Flood Map Service Center; Horry County Emergency Management, "Build Responsibly"; Horry County Code Enforcement, "When to get a Building Permit"; S.C. Code of Laws, Title 40, Chapter 59 (sections 40-59-20, 40-59-30 and 40-59-260); S.C. Code of Laws, Title 6, Chapter 9 (sections 6-9-50 and 6-9-60); S.C. Code Regs. 8-1202; SC Building Codes Council, "2021 South Carolina Code Adoptions" and llr.sc.gov/bcc; SC LLR, Residential Builder License and the public license lookup; EPA, Renovation, Repair and Painting Program for contractors and the lead safe certified firm search; South Carolina Residential Code 2021, sections R102.7.1, R105.1, R105.2, R109, R301.2.1 and R322.1 (code reproduction, confirm with your jurisdiction: chapter 1, chapter 2, chapter 3).