Blown-in insulation cost guide 2026: what to expect to pay

Blown-in insulation is one of the most popular and cost-effective ways to improve your home’s energy efficiency. Whether you are topping off a thin attic layer or filling wall cavities in an older home, understanding the costs upfront helps you budget accurately and avoid surprises.

This guide covers national averages, detailed cost breakdowns by project type, the factors that drive pricing up or down, and practical ways to save money on your blown-in insulation project.

Quick answer: blown-in insulation costs

The national average cost for blown-in insulation is $1.00 to $2.50 per square foot installed, with most homeowners paying around $1.75 per square foot. For a typical 1,500-square-foot attic, that works out to $1,500 to $3,750 for a complete installation.

These figures include both materials and professional labor. Your actual cost will vary based on the material you choose, the R-value required for your climate zone, and how accessible the installation area is.

Detailed cost breakdown by project type

Blown-in insulation pricing varies depending on where in your home the work is being done and what material is used. Here is what to expect for the most common project types.

Attic blown-in insulation

Attic insulation is the most straightforward blown-in project. The space is usually accessible through a hatch or pull-down stairs, and the work involves blowing loose material over the attic floor to the desired depth.

Cellulose typically costs slightly more per square foot than fiberglass because it offers a higher R-value per inch. However, the price difference is small, and both materials perform well in attic applications. Read our complete attic insulation guide for help choosing the right material.

Wall cavity blown-in insulation

Filling wall cavities in an existing home is more labor-intensive than attic work. The contractor drills small holes in the exterior siding or interior drywall, inserts a fill hose, blows the insulation to the proper density, and patches the holes.

Expect to pay $1.50 to $3.00 per square foot for wall cavity blown-in insulation. The higher cost reflects the additional labor for drilling, filling, and patching. A typical 2,000-square-foot home with uninsulated walls costs $3,000 to $6,000 for a complete wall insulation retrofit.

Garage blown-in insulation

Insulating an attached garage helps buffer the living space from outdoor temperatures. A two-car garage ceiling (roughly 400-500 sq ft) costs $400 to $1,250 for blown-in insulation, depending on the material and thickness.

Factors that affect blown-in insulation cost

Several variables determine where your project falls within the cost ranges above. Understanding these factors helps you anticipate your final price when comparing contractor quotes.

Material choice

Blown-in insulation comes in two main materials, each with different costs and performance characteristics.

Cellulose is made from recycled paper products treated with fire retardants. It provides R-3.2 to R-3.8 per inch and costs slightly more than fiberglass. Its higher R-value per inch means you need less depth to hit your target R-value.

Fiberglass is made from spun glass fibers. It delivers R-2.2 to R-2.7 per inch and costs slightly less than cellulose. Fiberglass resists moisture better and does not settle as much over time.

For a deeper comparison of insulation materials, see our R-value guide.

Area size and square footage

Larger projects cost more in total but often have a lower cost per square foot. Contractors can spread their setup time and equipment costs across more area, which brings down the per-unit price. A 2,000-square-foot attic project will typically cost less per square foot than a 500-square-foot project.

Accessibility

Easy attic access through a standard pull-down staircase keeps costs low. Tight or hard-to-reach spaces, such as cathedral ceilings, enclosed soffits, or low-clearance attics, increase labor time and cost.

Wall cavities require drilling from the interior or exterior, which adds significant labor. Multi-story homes cost more because upper floors require scaffolding or ladder work.

Existing insulation removal

If your current insulation is contaminated by mold, moisture damage, or pest droppings, it needs to be removed before new material goes in. Insulation removal adds $1.00 to $2.00 per square foot to the project cost. Clean, dry existing insulation can typically stay in place with new material blown on top.

Climate zone and R-value requirements

Homes in colder climates need higher R-values, which means more insulation material. An attic in climate zone 1 (southern Florida) needs R-30, while zone 6 and 7 attics (Minnesota, Maine) need R-49 to R-60. More material means higher costs.

Check the Department of Energy’s recommended R-values for your area, or read our R-value guide by climate zone for a complete breakdown.

Geographic location and labor rates

Labor rates vary by region. Metropolitan areas like San Francisco, New York, and Denver tend to have higher contractor rates than smaller cities and rural areas. Material costs can also vary by 10% to 20% depending on local supply and demand.

How to save money on blown-in insulation

Blown-in insulation is already one of the most affordable insulation options, but there are ways to stretch your budget further.

Get multiple quotes

Comparing quotes from at least three insulation contractors gives you a realistic picture of fair market pricing. Be specific about the scope of work when requesting quotes so you can make accurate apples-to-apples comparisons.

Take advantage of tax credits and rebates

The federal Inflation Reduction Act offers a tax credit of up to 30% of insulation costs, capped at $1,200 per year. Many state and local utilities offer additional rebates for energy efficiency upgrades. These incentives can reduce your effective cost by hundreds of dollars.

Schedule during the off-season

Demand for insulation peaks in late fall before winter. Scheduling your project in late spring or summer can sometimes get you better pricing and faster availability from contractors.

Consider a top-off instead of full replacement

If your existing attic insulation is clean and dry but just too thin, adding blown-in insulation on top is far cheaper than removing everything and starting fresh. Topping off an attic from R-19 to R-49 costs significantly less than insulating from zero.

Bundle with other energy upgrades

Some contractors offer discounts when you combine insulation with air sealing, duct sealing, or other energy efficiency work. Bundling also makes it easier to qualify for utility rebate programs that require a whole-home approach.

For more ways to finance your insulation project, see our home improvement financing guide.

ROI and energy savings

Blown-in insulation delivers one of the best returns on investment of any home improvement. Here is what the numbers look like.

Energy bill savings

The Department of Energy estimates that adding insulation and sealing air leaks can reduce heating and cooling costs by 15% to 30%. For a household spending $2,400 per year on energy, that translates to $360 to $720 in annual savings.

Attic insulation upgrades produce the largest savings because heat rises and escapes most readily through an under-insulated roof. A properly insulated attic can reduce heat loss through the ceiling by up to 75%.

Payback period

Most blown-in attic insulation projects pay for themselves within two to four years through energy savings alone. The payback period depends on your current insulation level, energy costs, and climate. Homes in cold climates with little existing insulation see the fastest returns.

Home value impact

Energy-efficient upgrades increase your home’s marketability. Buyers pay attention to utility costs, and homes with documented insulation upgrades often sell faster. While insulation alone may not dramatically increase appraised value, it contributes to the overall energy performance that buyers value.

Comfort improvements

Beyond dollar savings, blown-in insulation makes your home noticeably more comfortable. Rooms stay at more consistent temperatures, drafts decrease, and your HVAC system runs less frequently. These quality-of-life improvements are hard to put a dollar value on, but homeowners consistently rank them as the most satisfying outcome of an insulation upgrade.

Find blown-in insulation contractors by state

Get free quotes from qualified insulation contractors in your area:

• Utah insulation contractors | Salt Lake City
• Idaho insulation contractors | Boise
• Colorado insulation contractors | Denver
• Oregon insulation contractors | Portland
• North Carolina insulation contractors | Charlotte | Raleigh
• Tennessee insulation contractors | Nashville
• Florida insulation contractors | Tampa
• Arizona insulation contractors | Phoenix
• Ohio insulation contractors | Columbus

Frequently asked questions

For more information on insulation options, read our spray foam vs. fiberglass comparison, our attic insulation guide, or our R-value guide. Visit our insulation contractor hub to find qualified pros in your area.