Everetts, NC
6 miles west
144 people, under a tenth of Williamston's population
Attic insulation in EverettsAttic Insulation in Williamston, NC
Blown-in attic insulation for Williamston, NC, in Martin County, plus removal and air sealing.
About Williamston and Its Homes
Williamston, the Martin County seat on the Roanoke River, was incorporated in 1779 and rebuilt its downtown after the railroad came in 1882 and peanuts and tobacco took off. Much of its historic residential district filled in during the 1910s and 1920s, in frame bungalows and dormered cottages.
Williamston, in Martin County, fell from 5,222 people in 2020 to 5,086 in 2025 (Census Bureau estimates), on 4.51 square miles. No town in Martin County has more people than Williamston.
Williamston has about 2,800 housing units, 25 percent of Martin County's; about 51 percent of the town's households own their home. About 2,400 of those 2,800 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 2,400.
Williamston at a Glance
- County: Martin County
- Population: 5,086 (2025), 5,222 (2020), down 2.6%
- Land area: 4.51 square miles (1,128 people each)
- Housing units: about 2,800 (±236)
- Median year built: 1962 (±4); Martin County: 1975
- Owner-occupied: 51% (±9); Martin County: 67%
- Detached houses: 73% (±8); Martin County: 68%
- Apartments: 27% (±7)
- Climate zone: 3 on both maps
- ENERGY STAR target for Williamston attics: R-49 from bare, R-38 over 3 to 4 inches (R-value guide)
Census Bureau estimates for Williamston, 2020 to 2024 (± margin of error).
Williamston Homes and Their Attics
Dormered Colonial Revival Cottages
The 2001 nomination for the Williamston Historic District counts several dozen one and one-and-a-half-story Colonial Revival cottages, built between 1927 and 1942 for middle-income families. The most common form has a gable roof with three gable dormers. A story-and-a-half bungalow with one big dormer over an engaged porch is common there too. In both, the upstairs bedrooms tuck under the rafters, and short knee walls mark off the low sides. Behind those walls lie narrow wedges of attic that an Iowa training text on house construction problems singles out as often leaky. We seal the gaps there, then insulate the wedges along with the flat ceiling above.
Brick Ranches of the Postwar Years
After World War II, brick veneer grew especially popular for new ranch houses in Williamston, the district nomination observes. Its inventory lists more than twenty one-story ranches, nearly all brick, built from 1946 into the 1970s, some under low hipped roofs. As the housing figures on this page show, more than half of the homes in town predate 1970. A low roof leaves very little room where the attic meets the outside walls. ENERGY STAR cautions that insulation often runs thin at the eaves even where the center looks deep enough. We fit baffles at the soffit vents so they stay open, then fill the edges to the same depth.
Attic Insulation in Williamston
About 65 percent of Williamston's homes predate 1970; if your joists show above the insulation, ENERGY STAR says to add more insulation.
Built from 1940 to 1969, before the state's 1978 insulation rule, about 55 percent of Williamston homes often have little insulation.
The Local Climate
Williamston's center sits about 70 feet above sea level, 1 mile from NOAA's Williamston 1 E station, the best match for Williamston. The station's 1991 to 2020 normals average about 3,030 heating and 1,770 cooling degree days a year, so at Williamston's station, heating needs outweigh cooling.
Homes by Age: What It Means for the Attic
About 73 percent of Williamston housing units are detached single-family houses.
Built from 1970 to 1989, about 25 percent of Williamston homes may hold settled fiberglass; check its depth against the joists.
About 27 percent of Williamston units sit in buildings of two or more homes, where the attic is often shared.
Homes by Year Built
- Before 1940: 12% (±7), about 330 units
- 1940s: 9% (±4), about 250 units
- 1950s: 27% (±7), about 750 units
- 1960s: 18% (±7), about 510 units
- 1970s: 13% (±5), about 370 units
- 1980s: 11% (±4), about 320 units
- 1990s: 4% (±3), about 120 units
- 2000s: 5% (±3), about 130 units
- 2010s: 2% (±1), about 45 units
- 2020 or later: under 1%
Air Sealing and Duct Sealing in Williamston
In Williamston, about 73 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: 73% (±8), about 1,730 households; Martin County: 66%
- Piped gas: 2% (±2), about 55 households
- Bottled or tank gas: 19% (±7), about 460 households
Power, Gas and Rebates
Dominion Energy North Carolina supplies Williamston's electricity. For gas, Williamston is in the Martin County franchise of Piedmont Natural Gas, whose mains may not reach every street in Williamston. Dominion's rebate pays more for electrically heated homes, about 73 percent of Williamston's. Bottled or tank gas, bought by the delivery, heats about 19 percent of homes in Williamston.
Rebate to check in Williamston: Home Energy Evaluation (Dominion Energy's contractor network). Before a job in Williamston, check its current terms; the Martin County page lists every program.
Attic Insulation Removal in Williamston
In a Williamston attic, only wet, moldy or animal-soiled insulation is vacuumed out (ENERGY STAR's test), once the cause is fixed, and after mice that Williamston attic is sanitized and deodorized; dry, clean insulation stays.
Also Serving Near Williamston
Nearest to Williamston first.
Bear Grass, NC
7 miles southwest
81 people, under a tenth of Williamston's population
Attic insulation in Bear GrassJamesville, NC
10 miles east
411 people, under a tenth of Williamston's population
Attic insulation in JamesvilleHamilton, NC
10 miles northwest
Power from its own town system (Williamston: Dominion Energy North Carolina); 297 people, under a tenth of Williamston's population
Attic insulation in HamiltonRobersonville, NC
11 miles west
Median home built 1964 (Williamston: 1962); 1,237 people, about a quarter of Williamston's population
Attic insulation in Robersonville
Williamston Insulation FAQs
Do I need anyone's approval to insulate a house in the Williamston Historic District?
Not from the National Register. Williamston has two listed districts, the large residential one and the commercial blocks downtown. A listing does not tie the hands of an owner who keeps up a house with private funds, as the State Historic Preservation Office describes it. Its 2023 roster of local commissions has no entry for Martin County. Insulating and air sealing are interior work. If new roof vents are part of the plan, check with the town about outside changes first.
My Williamston house is older frame construction. What about the wiring up there?
Get it looked at before anything is covered. The district nomination says every house in it was frame until a brick one went up in 1915, and that much of the area was built in the 1910s and 1920s. Houses of that age may first have been wired with knobs and tubes, a system ENERGY STAR calls a fire hazard where insulation surrounds it. Our first step is an electrician's visit, and any run still carrying power stays uncovered.
Can a landlord in Williamston have a rental house's attic insulated?
Yes, that is the owner's call. Rentals are nothing new here: the district nomination notes that one-story Craftsman bungalows were especially popular as rental houses, and it lists pairs of rental houses from the 1930s and 1940s. The tenant only needs to give us access to the attic hatch. We seal the ceiling and add or replace the insulation from above.
Could the old insulation in a Williamston attic be vermiculite?
It could: about 45 percent of Williamston's homes predate 1960. If a Williamston attic holds a pebble-like gray-brown or silver-gold fill, leave it undisturbed: the EPA says vermiculite may contain asbestos.
Does attic insulation in Williamston need a permit?
Williamston Town Hall can say whether Martin County Building Inspections, the town itself or another office handles permits in Williamston; ask before work starts.
Sources
Census Bureau figures for Williamston, NOAA normals for the Williamston 1 E station, Dominion Energy North Carolina (October 2026). Compiled by Insulation Pros. How the town pages are made.
Sources for the Williamston notes and questions (read October 20, 2026):
- Williamston, in The North Carolina Gazetteer (William S. Powell, 2nd ed., UNC Press 2010), NCpedia
- Williamston Commercial Historic District, National Register nomination (NC HPO)
- Williamston Historic District, National Register nomination (NC HPO)
- Building Construction Problem Areas, weatherization training text, Iowa Department of Health and Human Services
- Attic Air Sealing Project, ENERGY STAR
- Year Structure Built (table B25034), Williamston town, American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau via Census Reporter
- Adding Attic Insulation, ENERGY STAR do-it-yourself guide
- About Attic Ventilation, ENERGY STAR do-it-yourself guide
- 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)
- Attic Insulation Project, ENERGY STAR
Williamston, NC
Open in Google Maps (opens in a new tab)Serving Williamston, NC
Insulation Pros is an insulation contractor serving North Carolina, Williamston and the rest of Martin County included.
Reach us
Send the square footage of your Williamston attic, or call (336) 870-3893.