Southport, NC
3 miles northeast
Median home built 2003 (Caswell Beach: 1998); Power from its own town system (Caswell Beach: Duke Energy Progress)
Attic insulation in SouthportAttic Insulation in Caswell Beach, NC
Blown-in attic insulation for Caswell Beach, NC, 3 miles from Southport, plus removal and air sealing.
About Caswell Beach and Its Homes
Caswell Beach, on the eastern end of Oak Island, had its vote on becoming a town called by the legislature in 1975. Hurricane Hazel had swept most buildings off the county's barrier islands in 1954, and the housing figures on this page show most homes here date from 1970 on.
Caswell Beach, in Brunswick County, fell from 389 people in 2020 to 381 in 2025 (Census Bureau estimates), on 2.97 square miles.
Caswell Beach has about 680 housing units, 1 percent of Brunswick County's; 93 percent of the town's households own their home. Only about 230 of those 680 units were someone's usual home in the Census Bureau's 2020 to 2024 survey; the heating and owner figures on this page describe those 230.
Caswell Beach at a Glance
- County: Brunswick County
- Population: 381 (2025), 389 (2020), down 2.1%
- Land area: 2.97 square miles (128 people each)
- Housing units: about 680 (±64)
- Median year built: 1998 (±3); Brunswick County: 2002
- Owner-occupied: 93% (±6); Brunswick County: 85%
- Detached houses: 56% (±8); Brunswick County: 69%
- Attached houses: 6% (±2)
- Apartments: 36% (±6)
- Mobile homes: 2% (±2)
- Climate zone: 3 on both maps
- ENERGY STAR target for Caswell Beach attics: R-49 from bare, R-38 over 3 to 4 inches (R-value guide)
Census Bureau estimates for Caswell Beach, 2020 to 2024 (± margin of error).
Caswell Beach Homes and Their Attics
A Rescue Station Turned Summer Cottage
One house in town began as the Oak Island Life Saving Station, built in 1889 on a standard government plan. Its National Register nomination, written in 2000, describes a story-and-a-half frame building with dormers and a rooftop lookout. It was sold around 1938, moved across the road and used as a summer cottage. The nomination notes a low attic reached by the original ladder stair. A cottage first used for summers may never have been insulated for the cold months, and later owners may or may not have added any. So look before assuming, all the way out to the low edges of the roof.
Low Beach Cottages and Taller New Houses
The 2010 county survey says most beach houses built before Hazel were simple. Its Caswell Beach example, probably from 1948, is one story on timber piers under a low shed roof. The survey contrasts it with the lofty houses of recent years and notes the loss of similar cottages to redevelopment. Whatever the size, a beach house attic needs the same two things. Bath, kitchen and dryer vents must carry damp air outdoors, never into the attic, and the soffit vents must stay open so outside air can move through. When insulation is added, baffles at the eaves keep it from blocking that airflow.
Attic Insulation in Caswell Beach
If the joists show above the insulation in a Caswell Beach attic, ENERGY STAR says to add more insulation.
From 1990 to 2009, about 60 percent of Caswell Beach homes were built to codes below ENERGY STAR's target; check their eaves, where ENERGY STAR says insulation is often thinnest.
The Local Climate
Caswell Beach's center sits about 20 feet above sea level, 7 miles from NOAA's Southport 5 N station, the best match for Caswell Beach. The station's 1991 to 2020 normals average about 2,200 heating and 2,230 cooling degree days a year, so Caswell Beach attics work in both seasons.
The state energy code marks Brunswick County warm and humid.
Homes by Age: What It Means for the Attic
About 56 percent of Caswell Beach housing units are detached single-family houses.
Built from 1970 to 1989, about 30 percent of Caswell Beach homes may hold settled fiberglass; check its depth against the joists.
About 36 percent of Caswell Beach units sit in buildings of two or more homes, where the attic is often shared.
Homes by Year Built
- Before 1940: under 1%
- 1940s: under 1%
- 1950s: 1% (±1)
- 1960s: under 1%
- 1970s: 4% (±2), about 25 units
- 1980s: 28% (±7), about 190 units
- 1990s: 22% (±5), about 145 units
- 2000s: 39% (±8), about 265 units
- 2010s: 6% (±3), about 40 units
- 2020 or later: under 2%
Air Sealing and Duct Sealing in Caswell Beach
In Caswell Beach, about 89 percent of households heat with electricity; where that heat is forced air, ducts often run through the attic.
Air sealing comes first, as the EPA advises: wire and pipe holes, wall tops and soffits.
How Homes Here Are Heated
- Electricity: 89% (±10), about 205 households; Brunswick County: 87%
- Piped gas: 3% (±3)
- Bottled or tank gas: 7% (±4), about 15 households
Power, Gas and Rebates
Duke Energy Progress supplies Caswell Beach's electricity. For gas, Caswell Beach is in the Brunswick County franchise of Piedmont Natural Gas, whose mains may not reach every street in Caswell Beach. Duke's free House Call fits many Caswell Beach homes: about 89 percent of households heat with electricity.
Rebate to check in Caswell Beach: Smart $aver Insulate and Seal (Duke Energy; Insulation Pros is an approved trade ally). Before a job in Caswell Beach, check its current terms; the Brunswick County page lists every program.
Attic Insulation Removal in Caswell Beach
In a Caswell Beach attic, only wet, moldy or animal-soiled insulation is vacuumed out (ENERGY STAR's test), once the cause is fixed, and after mice that Caswell Beach attic is sanitized and deodorized; dry, clean insulation stays.
Also Serving Near Caswell Beach
Nearest to Caswell Beach first.
St. James, NC
4 miles northwest
Median home built 2011 (Caswell Beach: 1998); 7,318 people, about 19 times Caswell Beach's population
Attic insulation in St. JamesOak Island, NC
4 miles west
Median home built 1997 (Caswell Beach: 1998); 9,337 people, about 25 times Caswell Beach's population
Attic insulation in Oak IslandBald Head Island, NC
5 miles southeast
Median home built 2002 (Caswell Beach: 1998)
Attic insulation in Bald Head IslandBoiling Spring Lakes, NC
10 miles north
Median home built 1998, as in Caswell Beach; 6,875 people, about 18 times Caswell Beach's population
Attic insulation in Boiling Spring Lakes
Caswell Beach Insulation FAQs
After a storm like Florence, how do I check my Caswell Beach attic?
From inside, before anything new goes on top. The National Weather Service says Florence, in September 2018, left Caswell Beach with downed trees and lost water and sewer service. Wind damage on Oak Island ran mostly to shingles and siding. A missing shingle can let rain soak the insulation under it. Look for ceiling stains and damp, matted insulation near the roof edges. If you find it, the roof is repaired first, then the wet insulation is replaced.
Do the lighthouse and old station listings put rules on my Caswell Beach house?
No. The two National Register listings in town are the Oak Island Lighthouse, which passed to the town in 2004, and the old rescue station. The State Historic Preservation Office explains that a listing does not restrict what an owner does with private funds. These two listings cover only those two places. The state's February 2023 roster shows no preservation commission in Brunswick County, so attic work is your call.
Does attic insulation in Caswell Beach need a permit?
Caswell Beach Town Hall can say whether Brunswick County Permits & Development, the town itself or another office handles permits in Caswell Beach; ask before work starts.
Helpful Guides
- Brunswick County is warm and humid by the state energy code: attic condensation and mold
- Power from Duke Energy Progress: high summer electric bills and home energy audits
- Hot summers at NOAA's Southport 5 N station: radiant barriers
Sources
Census Bureau figures for Caswell Beach, NOAA normals for the Southport 5 N station, Duke Energy Progress (October 2026). Compiled by Insulation Pros. How the town pages are made.
Sources for the Caswell Beach notes and questions (read October 20, 2026):
- Caswell Beach, in The North Carolina Gazetteer (William S. Powell, 2nd ed., UNC Press 2010), NCpedia
- Session Law 1975-293, An Act to Authorize an Election on the Question of Incorporating the Town of Caswell Beach, North Carolina General Assembly
- Session Law 1975-630, An Act to Modify the Dates for the Caswell Beach Incorporation Referendum, North Carolina General Assembly
- Comprehensive Historical and Architectural Survey of Brunswick County, 2009-2010 (listed by the NC HPO as the Brunswick County Survey, 2010)
- Year Structure Built (table B25034), Caswell Beach town, American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau via Census Reporter
- Oak Island Life Saving Station, National Register nomination (NC HPO)
- Attic Insulation Project, ENERGY STAR
- About Attic Ventilation, ENERGY STAR do-it-yourself guide
- Hurricane Florence, September 2018, event summary, National Weather Service Wilmington, North Carolina
- NC Listings in the National Register of Historic Places, NC State Historic Preservation Office
- Oak Island Lighthouse, National Register nomination (NC HPO)
- What Is the National Register of Historic Places?, NC State Historic Preservation Office
- Historic Preservation Commission Staff in North Carolina, listed by county, as of 2/20/2023 (NC HPO)
Caswell Beach, NC
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Insulation Pros is an insulation contractor serving North Carolina, Caswell Beach and the rest of Brunswick County included.
Reach us
Send the square footage of your Caswell Beach attic, or call (336) 870-3893.