Richlands, NC
15 miles northwest
Its NOAA station logs about 310 more heating degree days than Jacksonville's; 2,485 people, under a tenth of Jacksonville's population
Attic insulation in RichlandsInsulation Contractor Serving Jacksonville, NC
Blown-in attic insulation for Jacksonville, NC, in Onslow County, plus removal and air sealing.
About Jacksonville and Its Homes
Jacksonville, the Onslow County seat on the New River, was a small lumber and railroad town until Marine Corps Base Camp Lejeune was set up beside it in 1941. Its houses carry both stories: frame homes from the 1890s lumber boom near the river, and the much larger city that grew around the base.
Jacksonville, in Onslow County, fell from 73,158 people in 2020 to 72,732 in 2025 (Census Bureau estimates), on 48.8 square miles. No town in Onslow County has more people than Jacksonville.
Jacksonville has about 25,000 housing units, 29 percent of Onslow County's; 39 percent of the city's households own their home.
Jacksonville at a Glance
- County: Onslow County
- Population: 72,732 (2025), 73,158 (2020), down 0.6%
- Land area: 48.8 square miles (1,490 people each)
- Housing units: about 25,000 (±805)
- Median year built: 1992 (±3); Onslow County: 1998
- Owner-occupied: 39% (±3); Onslow County: 64%
- Detached houses: 49% (±2); Onslow County: 65%
- Attached houses: 21% (±2)
- Apartments: 28% (±4)
- Mobile homes: 2% (±1)
- Climate zone: 3 on both maps
- ENERGY STAR target for Jacksonville attics: R-49 from bare, R-38 over 3 to 4 inches (R-value guide)
Census Bureau estimates for Jacksonville, 2020 to 2024 (± margin of error).
Jacksonville Homes and Their Attics
The Mill Avenue Neighborhood by the New River
Mill Avenue was platted around 1890, soon after the Onslow Lumber Company was formed in 1889, and the railroad reached town in December 1890. Its 1989 National Register nomination describes late Victorian frame houses for the town's merchants, along with duplexes, worker housing, and bungalows from the 1920s and 1930s. Houses this old can hide knob-and-tube circuits, the open wiring used before about 1930. ENERGY STAR warns that insulation heaped over those old wires is a fire hazard. So on Mill Avenue the first visit to the attic is an electrician's, and any of that wiring still live stays bare.
A City Built Out Around Camp Lejeune
The county's National Register survey of historic resources says the base brought a surge of new residents and made Jacksonville the main center for the homes and stores that followed. Low-rise shops spread along New Bridge Street toward the base in the 1940s and 1950s. The housing figures on this page bear that out, with the larger part of the city's homes dating from 1970 on. Newer ceilings may hold recessed lights, so look at those before any insulation goes in. ENERGY STAR keeps insulation a full 3 inches back from cans without an IC rating. Fixtures rated IC may be buried.
Attic Insulation in Jacksonville
Some 24 percent of Jacksonville's homes predate 1970; if your joists show above the insulation, ENERGY STAR says to add more insulation.
From 1990 to 2009, 29 percent of Jacksonville homes were built to codes below ENERGY STAR's target; check their eaves, where ENERGY STAR says insulation is often thinnest.
The Local Climate
Jacksonville's center sits near sea level, 3 miles from NOAA's Jacksonville EOC station, the best match for Jacksonville. The station's 1991 to 2020 normals average about 2,770 heating and 1,880 cooling degree days a year, so Jacksonville attics work in both seasons.
Readings change over short distances around Jacksonville: NOAA's New River Marine Corps Air Facility station, 5 miles away, averages about 2,500 heating degree days. The state energy code marks Onslow County warm and humid.
Homes by Age: What It Means for the Attic
Some 49 percent of Jacksonville housing units are detached single-family houses.
Built from 1970 to 1989, 24 percent of Jacksonville homes may hold settled fiberglass; check its depth against the joists.
About 37 percent of Jacksonville's housing units predate 1980; nearly all predate the state's 1978 insulation rule too. Some 28 percent of Jacksonville units sit in buildings of two or more homes, where the attic is often shared. Renters hold 61 percent of Jacksonville's occupied homes, so many attic decisions rest with landlords.
Homes by Year Built
- Before 1940: 1% (±1), about 140 units
- 1940s: 3% (±1), about 850 units
- 1950s: 11% (±2), about 2,700 units
- 1960s: 10% (±1), about 2,400 units
- 1970s: 12% (±2), about 3,100 units
- 1980s: 12% (±2), about 3,000 units
- 1990s: 10% (±2), about 2,400 units
- 2000s: 19% (±3), about 4,900 units
- 2010s: 21% (±4), about 5,400 units
- 2020 or later: 2% (±1), about 420 units
Air Sealing and Duct Sealing in Jacksonville
In Jacksonville, 91 percent of homes 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: 91% (±2), about 21,000 households; Onslow County: 92%
- Piped gas: 6% (±2), about 1,410 households
- Bottled or tank gas: 2% (±1), about 420 households
Power, Gas and Rebates
Duke Energy Progress serves most of Jacksonville, Jones-Onslow EMC its edges; your bill says which. For gas, Jacksonville is in the Onslow County franchise of Piedmont Natural Gas, and 6 percent of the city's homes heat with piped gas. Duke's free House Call fits many Jacksonville homes: 91 percent heat with electricity.
Rebate to check in Jacksonville: Smart $aver Insulate and Seal (Duke Energy; Insulation Pros is an approved trade ally). Before a job in Jacksonville, check its current terms; the Onslow County page lists every program.
Attic Insulation Removal in Jacksonville
In a Jacksonville attic, only wet, moldy or animal-soiled insulation is vacuumed out (ENERGY STAR's test), once the cause is fixed, and after mice that Jacksonville attic is sanitized and deodorized; dry, clean insulation stays.
Also Serving Near Jacksonville
Nearest to Jacksonville first.
Swansboro, NC
15 miles east
Median home built 2002 (Jacksonville: 1992); Its NOAA station logs about 270 fewer heating degree days than Jacksonville's
Attic insulation in SwansboroMaysville, NC
15 miles northeast
Its NOAA station logs about 350 more heating degree days than Jacksonville's; 853 people, under a tenth of Jacksonville's population
Attic insulation in MaysvilleNorth Topsail Beach, NC
17 miles south
Median home built 1989 (Jacksonville: 1992); 1,097 people, under a tenth of Jacksonville's population
Attic insulation in North Topsail BeachCedar Point, NC
18 miles east
Median home built 2000 (Jacksonville: 1992); 1,825 people, under a tenth of Jacksonville's population
Attic insulation in Cedar Point
Jacksonville Insulation FAQs
Is there an approval step for attic work in the Mill Avenue Historic District?
Not because of the district. Mill Avenue was entered on the National Register in 1990, and according to the state preservation office, the Register by itself restricts nothing a private owner pays for privately. Its 2023 roster of commission staff lists Swansboro's as the only commission in Onslow County. If your attic would need new vents cut through the roof, that is outside work, so ask the city before that part.
After a hurricane, what tells me water reached my Jacksonville attic?
Check the insulation beneath each spot where the roof took a hit. Insulation that is soggy, packed flat or water stained is the giveaway. Writing up Florence in 2018, the National Hurricane Center put Jacksonville among the places hardest hit by its flooding and described wind damage across Onslow County. ENERGY STAR reads wet insulation as a leaking roof. So the roofer comes first, and only then do we vacuum out the ruined insulation and blow in new.
I own a rental near the base. Can I have its attic insulated?
Yes. The building's owner makes that call, and a tenant living there does not change it. A landlord can have the attic of a rental insulated or air sealed between leases or with someone at home. We agree the install day with you. The person renting just has to give us a clear way to the hatch, and everything we do happens above the ceiling.
Are there rebates for attic insulation in Jacksonville?
Duke Energy's Smart $aver Insulate and Seal is the one to check: a rebate for attic insulation done together with air sealing, and a separate one for duct sealing, when the attic starts at R-19 or less; a contractor in Duke's Smart $aver network must do the work, and Insulation Pros is an approved Duke Energy trade ally. Check its current terms. The Onslow County page lists every other program.
How do I choose an insulation company in Jacksonville?
Compare written estimates for your Jacksonville attic listing air sealing, any removal and the added depth; for Duke Energy's rebate the contractor must be in Duke's network, and Insulation Pros is an approved Duke Energy trade ally.
Does attic insulation in Jacksonville need a permit?
Jacksonville City Hall can say whether Onslow County Building Guides, the city itself or another office handles permits in Jacksonville; ask before work starts.
Helpful Guides
- Onslow County is warm and humid by the state energy code: attic condensation and mold and attic ventilation
- Power from Duke Energy Progress: high summer electric bills and home energy audits
Sources
Census Bureau figures for Jacksonville, NOAA normals for the Jacksonville EOC station, Duke Energy Progress (October 2026). Compiled by Insulation Pros. How the town pages are made.
Sources for the Jacksonville notes and questions (read October 20, 2026):
- Jacksonville, in The North Carolina Gazetteer (William S. Powell, 2nd ed., UNC Press 2010), NCpedia
- Mill Avenue Historic District, National Register nomination (NC HPO)
- Historic and Architectural Resources of Onslow County, North Carolina, National Register multiple property documentation form (NC HPO)
- Attic Insulation Project, ENERGY STAR
- Year Structure Built (table B25034), American Community Survey 2024 5-year estimates, Jacksonville city, via Census Reporter
- NC Listings in the National Register of Historic Places, NC State Historic Preservation Office
- 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)
- Tropical Cyclone Report: Hurricane Florence (AL062018), National Hurricane Center
Jacksonville, NC
Open in Google Maps (opens in a new tab)Serving Jacksonville, NC
Insulation Pros is an insulation contractor serving North Carolina, Jacksonville and the rest of Onslow County included.
Reach us
Send the square footage of your Jacksonville attic, or call (336) 870-3893.