

Attic insulation, air sealing, crawl spaces and walls for homes in McClellanville — starting with a free assessment that measures the R-value you actually have. The typical home here dates to the mid-1980s, and 15% of its 357 homes went up before 1940.






McClellanville runs to about 2.2 square miles and roughly 690 people. It sits about 34 miles northeast of downtown Charleston. Around 357 housing units sit inside those boundaries. The community dates back to 1926. We cover ZIP code 29458.
No completed job in McClellanville is logged in our records yet, and this page will say so until one is.
The typical home in McClellanville dates to around the mid-1980s. Houses of this vintage usually got batts or blown fiber at whatever the standard of the day was, which is well short of what is recommended now. Most are one top-up away from being right.
The historic district holds about 105 mostly wood-frame buildings from about 1860 to 1935, mainly central-hall farmhouses plus Carpenter Gothic, Queen Anne and Italianate houses.
McClellanville is a small shrimping and fishing village on Jeremy Creek, surrounded by the Francis Marion National Forest, with town limits reaching the Intracoastal Waterway beside the Cape Romain National Wildlife Refuge. It began in the late 1850s-1860s as a pineland summer retreat for planters. Hurricane Hugo's eyewall passed directly over the village in 1989, destroying homes, toppling century-old oaks and pushing a storm surge into town.
The Census Bureau estimates 357 homes in McClellanville. 54 of them (15%) went up before 1940 — the 2nd-highest share of pre-1940 housing among the 28 places on this site. The 1970s were the busiest decade, adding 63 of today's homes (18%); 46% predate 1980 and 28% were built in 2000 or later. For Charleston County as a whole the pre-1940 share is 5%, so McClellanville sits above it.
Of 286 occupied homes, 1% heat with utility gas and 90% with electricity; another 9% burn propane or other tank gas. Electric heat here is more common than across the county (76%), and ranks 7th of 28 on this site. That is why the assessment asks how the house is heated: the fuel and the name on the utility bill decide which program, if any, can pay toward the work.
96% of occupied homes are owner-occupied and 97% of all homes are single-family detached houses. Read together, those numbers point toward an energy assessment before deciding what to fix first.
| Built | Homes | Share | |
|---|---|---|---|
| Before 1940 | 54 | 15% | |
| 1940s | 21 | 6% | |
| 1950s | 18 | 5% | |
| 1960s | 9 | 3% | |
| 1970s | 63 | 18% | |
| 1980s | 34 | 10% | |
| 1990s | 58 | 16% | |
| 2000s | 55 | 15% | |
| 2010s | 30 | 8% | |
| 2020 or later | 15 | 4% |
357 homes, Census ACS 2020–2024 (B25034, B25040, B25003); 286 occupied.
92 of McClellanville's 357 homes (26%) were built in the 1980s and 1990s. The gaps in houses of that age are the parts nobody sealed: batts stuffed into the rim joist, bare spots over cathedral and tray ceilings, soffit vents buried with no baffles, can lights punched through the ceiling plane. A top-up plus a day of sealing usually covers it.

McClellanville enforces the South Carolina Energy Standard (the 2009 IECC), by state law. Town code says the town enforces the mandatory codes the South Carolina Building Codes Council prescribes, with SAFEbuilt doing plan review and inspections.
For new work, the attic number under that edition is R-30, with walls at R-13. Set that against the Department of Energy, which recommends R49 for an uninsulated attic in this climate zone and R38 for one that already has a few inches.
Table 402.1.1 of the 2009 IECC, climate zone 3, which South Carolina's Energy Standard Act adopts for the whole state (section 6-10-30 of the South Carolina Code).
McClellanville requires a permit for this work. Town code makes it unlawful to "erect, modify, repair or add to any building" in McClellanville without first getting a permit from the town, and no exemptions are listed. Building permits are applied for online through the town's Community Core portal, with SAFEbuilt doing plan review and inspections. We pull it as part of the job.
The published number is 843-887-3712. The department page is here.
Permitting is on us, not on you.
Part of McClellanville sits inside Berkeley Electric Cooperative's territory, by the cooperative's own map, and Dominion Energy South Carolina is also on record in Charleston County: check whose name is on the electric bill first. Dominion Energy South Carolina's Check-up Plus is the big one: 90% of attic insulation, air sealing and duct sealing paid, up to $2,880, until March 31, 2027, for electrically heated homes that have had the free check-up, with the work done by Dominion's approved contractor.
Berkeley Electric lends rather than rebates: its HomeAdvantage program lends up to $20,000 at 5%, with an energy audit first and the payments added to the electric bill. Income-qualified households can apply to Palmetto Community Action Partnership (843-720-5336) for free weatherization instead. The Charleston County page and the rebate guide carry the full rules.
Every layer of an insulated attic, explained



McClellanville borders Francis Marion National Forest, Cape Romain National Wildlife Refuge, Jeremy Creek and Intracoastal Waterway.
Elsewhere in Charleston County we also cover:
South Carolina sets the residential energy code statewide, so the attic figure is R-30 wherever it is published here; what changes is the permit desk, and 7 of the 7 publish a permit rule for insulation.
| City | Energy code | Attic R required | Permit to insulate | Building dept. |
|---|---|---|---|---|
| McClellanville | 2009 IECC (state law) | R-30 | Yes | 843-887-3712 |
| Adams Run | 2009 IECC (state law) | R-30 | Yes | 843-202-6930 |
| Awendaw | 2009 IECC (state law) | R-30 | Yes | 843-202-6930 |
| Charleston | 2009 IECC (state law) | R-30 | Yes | 843-577-5550 |
| Unincorporated Charleston County | 2009 IECC (state law) | R-30 | Yes | 843-202-6930 |
| Edisto Island | 2009 IECC (state law) | R-30 | Yes | 843-202-6930 |
| Folly Beach | 2009 IECC (state law) | R-30 | Yes | 843-588-2447 |
All 22 Charleston County jurisdictions side by side →
McClellanville enforces the 2009 IECC (state law), which sets R-30 for an attic in new work. Whether it reaches a retrofit of an existing house is not published.
Yes. McClellanville requires a permit for this work, and we pull it as part of the job.
Dominion Energy South Carolina's Check-up Plus pays 90% of attic insulation, air sealing and duct sealing, up to $2,880, until March 31, 2027, for electrically heated homes; the program's contractor does the work. Berkeley Electric members get a 5% on-bill loan instead of a rebate. The federal 25C credit ended for work placed in service after December 31, 2025.
The typical home in McClellanville dates to around the mid-1980s; the Census Bureau's 2020-2024 median year built is 1984. Of its 357 homes, 15% went up before 1940 and 28% in 2000 or later. It is a median for the place, not a survey of individual houses.
Code and permit facts checked October 24, 2026, rebates October 24, 2026; housing: Census ACS 2020–2024. Sources: mcclellanvillesc.org (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15) · charlestoncounty.gov · scstatehouse.gov (2) · en.wikipedia.org (2) · nationalregister.sc.gov · dominionenergy.com · berkeleyelectric.coop · santeecooper.com · coastal.coop · energystar.gov · data.census.gov. These change; confirm with the building department at 843-887-3712 or the utility named on your electric bill first.

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