Attic Insulation in Myrtle Beach, SC

ENERGY STAR's retrofit table for climate zone 3 says R49 for an uninsulated attic, or add R38 if the attic already has 3 to 4 inches of insulation. The U.S. Department of Energy's county guide lists Horry and Georgetown counties as climate zone 3A (hot-humid). ENERGY STAR notes its table is based on the 2021 International Energy Conservation Code, Table R402.1.3.

Look across the attic. ENERGY STAR says that if the insulation is level with or below the floor joists, you probably need more; if you cannot see any joists because the insulation is well above them, you probably have enough. Check the eaves too, because insulation is often thin there even when the middle of the attic is full.

ENERGY STAR does not rank one material as the most cost-effective. Its R-value table shows the levels of insulation that are cost-effective for each climate, so the level matters more than the brand. You do not have to match what is already there: loose fill can go over batts, and unfaced batts can go over loose fill. Loose fill needs a blowing machine, which is why ENERGY STAR suggests a professional may be wise for it.

By state law (S.C. Code Section 6-10-30), the 2009 edition of the International Energy Conservation Code is South Carolina's Energy Standard, and all new and renovated buildings and additions must comply with it. The Building Codes Council's 2024 code adoption notice, with the new codes taking effect January 1, 2027, repeats that the 2009 IECC remains the energy standard by statute. ENERGY STAR's retrofit recommendations are based on the newer 2021 IECC, so they are higher than what the state standard sets as a minimum.

For climate zone 3, ENERGY STAR's main R-value table lists R49 for an empty attic; R60 is the level it lists for colder zones, 4 through 8. Its DIY checks page gives a wider range of R30 to R60 for zone 3. So R60 is within ENERGY STAR's range for our climate but above the 2021 IECC-based level for it.

EPA estimates that homeowners can save an average of 15% on heating and cooling costs, or an average of 11% on total energy costs, by air sealing their homes and adding insulation in attics, floors over crawl spaces and basements. That figure is for sealing and insulating together, not insulation alone. ENERGY STAR also says 9 out of 10 U.S. homes are under-insulated.

Yes. ENERGY STAR's DIY guide calls blocking the airflow at the eaves the most common mistake: never cover soffit vents with insulation, use rafter vents instead. Other mistakes on ENERGY STAR's pages: laying insulation over recessed lights that are not IC-rated, putting faced fiberglass over loose fill (it should be unfaced), and insulating over wet insulation from a roof leak.

Not under the federal Energy Efficient Home Improvement Credit. The IRS page (last reviewed April 28, 2026) says you can claim it for improvements made through December 31, 2025. Insulation installed in 2026 does not qualify. Some older pages still advertise the credit, so check the IRS page before counting on it. This is general information, not tax advice; ask your tax preparer about your situation.

Call (843) 877-5539 and ask. Tell us what is in the attic now, roughly how deep it is, and whether you have seen leaks or damp spots, and we will tell you on the phone whether your attic insulation job is one we handle. Our free roof inspection includes an attic assessment that looks at leaks, mold and mildew, and the condition of the insulation.

ENERGY STAR estimates 1 to 2 days when a contractor does the job, and 1 to 3 days if you do it yourself. Air sealing, baffles at the eaves and any roof or vent repairs come first and can add time.