How Much Does Blown-In Insulation Installation Cost in 2025?

This article was updated using automation technology and thoroughly reviewed for accuracy by HomeAdvisor Editor Ryan Noonan.

Blown-in insulation costs an average of $1,651, with most homeowners spending between $981 and $2,320. Your total cost will depend on the size of the area you need to insulate, the type of insulation you choose, and whether you hire a professional or tackle the project yourself.

At $1.75 to $7.50 per square foot, blown-in insulation (also called loose fill) is an effective way to improve your home's energy efficiency and fire protection. Let's break down the factors that influence the cost and the benefits you can expect.

Blown-In Insulation Cost per Square Foot

Blown-in insulation costs between $1.75 and $7.50 per square foot, depending on the insulation type. The price varies based on the R-value—the measure of how well the insulation resists heat flow. For optimal energy efficiency, aim for a minimum R-value of 30, which typically requires 10 to 14 inches of insulation material.

Keep in mind that your cost per square foot may increase if your project involves insulating areas around electrical wiring or outlets, as you might need to hire an electrician for safety reasons.

Blown-In Insulation Cost by R-Value

The R-value measures how well insulation resists heat flow—a crucial factor in determining your blown-in insulation cost. Higher R-values mean better insulation but also higher material costs.

The U.S. Department of Energy recommends the following levels of insulation:

• Floors and Crawl Spaces: R-13–R-30

• Walls: R-13–R-23

• Ceilings and Attics: R-30–R-60

Here's how the pricing breaks down for different R-values of blown-in wall insulation:

Blown-In Insulation Costs by Type

The type of blown-in insulation you choose affects both the cost and the efficiency of your project. Different materials have varying prices and installation times. Here's what you can expect to pay per square foot for each type:

Rockwool Fiber

Rockwool fiber, also known as mineral wool, costs between $1.40 and $2.10 per square foot and is slightly more expensive than cellulose. Made from rock and slag fibers, it's a sustainable and recyclable option.

Benefits of mineral wool include:

• Excellent acoustic control to reduce noise

• Natural pest repellent properties

• Noncombustible for added safety

• High heat insulation for better energy efficiency

• Moisture resistance to prevent mold

• Suitable for DIY projects

Cellulose

Blown-in cellulose is often more expensive than fiberglass and costs about $1.20 per square foot. The cellulose insulation cost per bag is typically around $30 to $40. It consists of recycled materials like newspaper and cardboard. The higher the R-value, the more you’ll pay for each project. Cellulose insulation comes in damp-spray and dense-pack options.

While damp-spray cellulose doesn't appear as tightly pressed to walls as dense-pack, each material is rated similarly in terms of its insulation abilities. The difference often comes down to the manufacturer or insulation company you choose.

Wet Blown-In Cellulose

Wet-spray insulation runs from $0.60 to $1.80 per square foot to install. Wet installations, which are sprayed and have short dry times, work best for new constructions when additional projects are going on around the insulation work.

Like other forms of insulation, it's fire retardant. It costs slightly less than dense-pack cellulose because it takes longer to dry and may leave gaps if not installed professionally.

Dense-Pack Cellulose

Dense-pack cellulose, which is air blown but dry when installed, is more costly at $2.00–$2.30 per square foot when you hire a pro to install it. Because of its high R-value, it works best in older homes, which may be more susceptible to letting hot or cool air escape. The installation process is less disruptive to surrounding structures than wet installation, but it may take longer.

Fiberglass

Fiberglass insulation runs from $500 to $1,100 to cover 1,000 square feet. The price per job varies based on the R-value of the insulation and the size of the project. Unlike cellulose, there are many options to choose from. Blown-in insulation increases your home’s energy efficiency and can help save money over time.

For a bag weighing 28 1/2 pounds, at an average cost of $30 to $70 per bag, a breakdown of R-value, number of bags, and material cost appear in the following table.

Additional Cost Factors

From hiring a pro to the strength and thickness of your blown-in insulation, some factors change the price you pay for your insulation.

Labor

Labor costs for installing insulation range from $40 to $70 per hour. If you have an older home, installation might cost more due to potential challenges like outdated structures or limited access. Choosing thicker insulation will also increase costs because it requires more material and takes longer to install.

New Construction vs. Replacement

With new blown-in insulation, you've got labor and material costs to cover based on square footage. Replacing insulation can be different because you're unlikely to spray vast areas with no insulation. Instead, you’re likely to fill gaps and cracks, which will take less time and require fewer materials.

When installed properly, blown-in insulation is rated to last between 60 and 80 years.

Mold and Asbestos Remediation

It's a common misconception that mold can grow in blown-in insulation. However, mold and asbestos can form on top of dust or other particles if it falls from a roof or another object.

On average, mold remediation costs $10 to $25 per square foot, while asbestos removal costs $1,200 to $3,300. For safety reasons, a pro will not fix or add blown insulation until both are removed.

Repairs

Holes are often left behind when installing blown-in insulation. These holes allow for the natural expansion of the material and alleviate pressure. Fortunately, you can patch drywall using budget-friendly methods. You can use a small can of spray insulation to fill the hole, allow it to dry, and saw away any excess. Or simply cover it with putty and paint. You can use either method for under $30.

How Much Blown-In Insulation Do I Need?

To calculate how many bags of blown-in insulation you'll need:

• Measure the square footage of the area you want to insulate.

• Determine the recommended R-value for that area.

• Check how much coverage each bag of your chosen insulation provides.

• Divide your total square footage by the coverage per bag.

• Adjust the number of bags if your insulation's R-value is lower than recommended—you may need to add more material to achieve the desired insulation level.

Most manufacturers provide charts on the packaging to help you calculate the exact number of bags.

"It's important to know your regional specifications when deciding how much insulation to install. While R-30 is standard for temperate areas, the Department of Energy recommends R-38,” says Cati O’Keefe, Expert Home Building & Sustainability Contributor. “Homeowners in parts of the country that experience extreme climate may need to insulate their attics to R-60."

Benefits of Installing Blown-In Insulation

Blown-in insulation offers several advantages over traditional batt and roll insulation. It's faster and less labor-intensive to install, as it doesn't require cutting and fitting pieces into place. This not only saves time but can also reduce labor costs.

Benefits of blown-in insulation include:

• Extends the life of your roof and shingles

• Reduces energy bills by improving efficiency

• Eliminates cold and hot spots for consistent comfort

• Long-lasting performance, with a lifespan of up to 100 years

DIY vs. Hiring a Pro

If your insulation project covers a large area, involves electrical components, or feels beyond your expertise, it's wise to hire a local insulation professional. Blown-in insulation pros charge between $40 and $70 per hour and can install your insulation quickly and safely.

Experienced insulation professionals can:

• Identify and avoid hazards like mold, asbestos, and faulty wiring

• Detect wall blockages and navigate around studs, ducts, and hidden wires

• Ensure the insulation is installed correctly for maximum efficiency

Blown-In Insulation Machine Rental Prices

Renting a blow-in insulation machine costs about $100 to $200 per day, depending on the rental company. Some insulation manufacturers offer free machine rental when you purchase their products, which can save you money.

However, operating the machine requires some skill, and improper use can lead to uneven insulation or equipment damage. If you're unsure about handling the equipment, consider hiring a local insulation pro to ensure your project is completed safely and effectively.

How HomeAdvisor Gets Its Cost Data

No place is more important than your home, which is why HomeAdvisor connects homeowners with local pros to transform their houses into homes they love. To help homeowners prepare for their next project, HomeAdvisor provides readers with accurate cost data and follows strict editorial guidelines. We surveyed over 10,000 real customers about their project costs to develop the pricing data you see, so you can make the best decisions for you and your home. We pair this data with research from reputable sources, including the U.S. Bureau of Labor Statistics, academic journals, market studies, and interviews with industry experts—all to ensure our prices reflect real-world projects.