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Insulation Contractor Serving Decatur, Illinois and Macon County

Spray foam, blown-in, fiberglass, attic, crawl space, and commercial insulation for Decatur homes, businesses, and industrial facilities. Headquartered in Mattoon, serving Decatur and Macon County since 1974.

Insulation Services for Decatur, IL Homes and Buildings

Decatur is the second largest city in our service area, with approximately 68,000 residents and one of the oldest, most industrial housing stocks in central Illinois. The city sits 55 miles west of our Mattoon headquarters along Route 36, and we have been insulating Decatur homes, commercial properties, and industrial buildings since 1974.

Decatur's economy was built on manufacturing and agricultural processing. Caterpillar, Archer Daniels Midland, and Mueller Co. have driven employment and growth in this city for decades. That industrial foundation shaped the housing stock. The neighborhoods surrounding the city center, Lake Decatur, and the older industrial corridors are filled with homes built during Decatur's manufacturing peak from the 1920s through the 1960s.

Decatur Housing Stock

The median construction year for homes in Decatur is 1960, and nearly a third of the city's housing was built before 1950. These are the homes that need insulation the most.

The original insulation—rock wool, early fiberglass batts, or nothing at all—has long since stopped performing. Many of these homes have balloon-frame walls, uninsulated crawl spaces or basements, and attics with R-11 or less. The current Illinois energy code requires R-49 in attic ceilings for Climate Zone 5. The typical older Decatur home has a quarter of that.

Whether you own a 1920s bungalow near Millikin University, a postwar ranch along Oakland Avenue, or a home in the newer subdivisions near Mount Zion, we can assess your insulation and tell you exactly what it needs.

Insulation Challenges We See in Decatur Homes

Pre-1950 Homes (32% of Decatur's housing stock)

Decatur's oldest neighborhoods contain bungalows, American Foursquares, and early 20th century homes with balloon-frame construction. These homes often have zero wall insulation, thin or absent attic insulation, and basements or crawl spaces with no thermal treatment. Dense-pack cellulose in the wall cavities is the most effective retrofit for these homes. Combined with attic air sealing and blown-in insulation, these upgrades can cut heating costs by 25% or more.

1950s-1970s Homes (the bulk of Decatur's housing)

Ranch homes, split-levels, and bi-levels built during Decatur's industrial expansion. Most have fiberglass batt insulation in the attic (typically R-11 to R-19, well below today's R-49 standard) and partial wall insulation. The attic batts have compressed over 50 to 70 years. Rim joists are uninsulated. Crawl spaces have failing fiberglass batts hanging from floor joists. Attic blown-in insulation and rim joist spray foam are the highest-ROI upgrades.

Industrial and Commercial Buildings

Decatur's manufacturing heritage means the city has a significant inventory of commercial warehouses, production facilities, and mixed-use buildings. Many are steel-framed structures with minimal or failing insulation. We provide commercial and metal building insulation with the insurance coverage, crew capacity, and code documentation these projects require.

Lake Decatur Area Homes

Properties near Lake Decatur deal with higher humidity exposure than homes in other parts of the city. Crawl space encapsulation and basement wall insulation are particularly important in lakeside neighborhoods where ground moisture and ambient humidity are elevated.

Insulation Services We Provide in Decatur and Macon County

Spray Foam Insulation

Open-cell and closed-cell spray foam for attic rooflines, rim joists, crawl spaces, and new construction.

Blown-In Insulation

Blown-in cellulose and fiberglass for attic floors and dense-pack wall retrofits.

Attic Insulation

Air sealing and insulation upgrades. From R-11 to R-49 in a single day.

Crawl Space

Vapor barriers, wall insulation, and vent sealing. Critical for Lake Decatur area homes.

Fiberglass Insulation

Cost-effective batt and roll insulation for new construction walls.

Pole Barn Insulation

Spray foam for pole barns and agricultural buildings across Macon County.

Metal Building Insulation

Spray foam for steel-framed commercial buildings and warehouses.

Commercial Insulation

Offices, retail, warehouses, churches, schools, and industrial buildings.

Why Decatur Property Owners Choose Insulation Service LLC

55 Miles, Straight Shot on Route 36

Our Mattoon headquarters is 55 miles east on Route 36. We are not driving from Chicago or Springfield. Crews work in Decatur regularly, scheduling estimates within one to two business days.

50 Years in This Market

We have been insulating homes and buildings in Macon County since 1974. We understand the housing stock, the climate, and the specific challenges that Decatur's older industrial-era homes present.

Residential, Commercial & Industrial

Decatur needs all three. We insulate single-family homes, rental properties, commercial offices, warehouses, and industrial facilities with the same crew, standards, and insurance.

Fully Insured

General liability and workers' compensation on every project. Certificates of insurance and additional insured endorsements provided on request.

500+ Projects Completed

Five hundred residential, commercial, and agricultural insulation projects across central Illinois, including a significant number in Macon County.

Free Estimates, No Obligation

Detailed, written estimates at no cost. We show up, measure, assess, and provide a specific scope and price.

Nearby Areas We Serve from Decatur

In addition to Decatur and Macon County, we serve communities throughout central Illinois:

Mount Zion 10 miles southeast
Forsyth 5 miles north
Champaign 45 miles east
Mattoon 55 miles east (HQ)
Effingham 65 miles southeast
Taylorville 30 miles southwest
View All Service Areas →

Insulation Questions from Decatur Homeowners

Insulation Service for Decatur, IL

Contact Information

Headquarters

Serving Decatur from our Mattoon, IL office
706 Dewitt Avenue East
Mattoon, IL 61938

Hours

Monday – Friday: 7:00 AM – 5:00 PM
24/7 Emergency Support Available

Schedule Your Free Insulation Estimate in Decatur

Whether you own a pre-war bungalow near downtown, a ranch home on the east side, or a commercial building near the industrial corridor, we will assess your insulation needs and provide a detailed, written estimate. No cost, no obligation. 50 years of experience across central Illinois.