Want to significantly lower your energy bills while also keeping your home cozy in winter and cool in the summer? One of the best things you can do is make sure your attic is sufficiently insulated. In fact, insulating your attic can save up to 20 percent on your heating and cooling costs, according to the U.S. Department of Energy.
“We talk about the ABC’s of insulation,” says Taylor Webb, a construction consultant and insulation expert with Home Solutions of Iowa. “ABC refers to ‘attics, basements, and conditioned spaces,’ and that’s the order in which you’ll get the most bang for your buck when insulating your home. Since your attic is hot in the summer and cold in the winter, you need a good insulation barrier to stop that unconditioned air from transferring into the conditioned part of your home and vice versa.”
If you’re considering the DIY approach, realize that insulating an attic yourself requires a pretty advanced skill level, and read up to make sure you follow all of the necessary prep work, safety precautions, and guidelines for your area.
After consulting with our experts, we researched insulation products based on the type of material, ease of use for DIYers, and the material’s resistance value (R-value): the higher the R-value, the more the product insulates per inch. Our top pick is US Greenfiber R60 Blown-In Insulation Sound Barrier, which reduces sound as well as insulates.
Here are the best picks for the best attic insulation.
Best Overall: Greenfiber Sanctuary R-60 Blown-In Insulation Sound Barrier
Retards flames and repels rodents
Made from 85 percent recycled materials
Provides continuous insulation with no gaps
Doesn’t irritate exposed skin
Requires advanced DIY skills
Requires special machine
For attics, Webb recommends loose-fill, blown-in cellulose insulation made from recycled paper treated with flame-retardants and insecticides. “Cellulose insulation is generally less flammable than fiberglass insulation, and mice and other critters don’t like to nest in cellulose,” he says.
The manufacturer says this product reduces heating and cooling costs by up to 20 percent and has the added benefit of reducing sound by 60 percent. It’s made with 85 percent post-consumer paper and uses low-energy manufacturing practices.
Price at time of publish: $15
Best Blown-In Fiberglass: Owens Corning AttiCat Pink Expanding Fiberglass Blown-In Insulation System 27.5 lbs.
Made from 50 percent recycled materials
Provides continuous insulation with no gaps
May be easier for DIYers than blown-in cellulose insulation
Special machine required
Can irritate exposed skin
Blown-in fiberglass may be easier to DIY than blown-in cellulose and is less likely to clog the machine used to blow in the product. Each bag is designed to cover 110 square feet at an R-19 value. This product contains about 50 percent recycled content compared, with 85 percent recycled content for cellulose insulation. However, fiberglass insulation may irritate exposed skin.
The manufacturer, Owens-Corning, says a specially designed machine—with free rental when you purchase 10 bags or more—conditions the product by adding air pockets that give the material its insulating power. (The material is designed to insulate ancillary objects such as pipes.) Blowing it into the attic can take as little as 1 1/2 hours, the manufacturer says, adding that an entire 1,000-square-foot attic can be insulated in as little as four hours.
Price at time of publish: $40
Best Fiberglass Rolls: Owens Corning R-30 Unfaced Fiberglass Insulation Roll 15 in. x 25 ft.
No special machine required
Easier cleanup than blown-in insulation
Cuts and separates cleanly
No shaking required
Not designed specifically for attic floors
Air can transfer between gaps
Can irritate skin
For an attic installation, fiberglass rolls or batting aren’t optimal, compared with blown-in insulation. “Batting is really made for walls,” Webb says. But pink fiberglass rolls are widely recognized by consumers—remember the Pink Panther commercials?—and may seem significantly less daunting to DIYers than blown-in insulation, which requires renting a special machine and can create a lot of dust. Just make sure you select insulation rolls or batting with the correct R-value for your area of the country.
We like Owens Corning’s fiberglass rolls because we note it is easy to install and that it seems to separate cleanly and easily without a lot of waste. The manufacturer also says that this product absorbs noise, and users report that it makes a significant difference in room temperature.
Price at time of publish: $34
Best Radiant Barrier: Reflectix Attic Unfaced Reflective Roll Insulation Individual Pack
Easier DIY than other insulation
No special tools required
Not considered as insulation
Unlike other insulation products installed on attic floors in hot and cold climates, radiant barriers are applied to the underside of roof rafters in hot climates, reducing heat gain and air conditioning usage. Also unlike other insulation applications, radiant barriers can be a true DIY solution. Generally, they are lightweight and easy to manage, generally requiring just a pair of scissors and a staple gun to install, and easy to clean up.
We recommend Reflectix Attic Unfaced Reflective Roll Insulation, which is specifically designed to be installed in attics, according to the manufacturer. The .006-inch-thick polyethylene fabrice requires only basic tools to install such as a staple gun, tape measure, and scissors. The product, which is fire-rated at class A/Class 1, is also formaldehyde-free.
Price at time of publish: $69
We believe the best type of attic insulation is blown-in cellulose, because it generally carries a higher R-value than other material. “Cellulose is usually about 3.5 R-value per inch, where fiberglass is about 2.5 R-value per inch,” says Taylor Webb, a construction consultant and insulation expert with Home Solutions of Iowa. Our Best Overall choice is US Greenfiber R60 Blown-In Insulation Sound Barrier. For blow-in fiberglass insulation, we recommend Owens-Corning AttiCat Pink Expanding Fiberglass Blown-In Insulation, which may require less-complex installation than blown-in cellulose.
What to Look for in Attic Insulation
Attic insulation comes in two basic types: Cellulose and fiberglass. “Cellulose is usually about 3.5 R-value per inch, where fiberglass is about 2.5 R-value per inch, says Taylor Webb, a construction consultant and insulation expert with Home Solutions of Iowa.
Cellulose takes the form of densely packed independent fragments of boric-acid-treated recycled ground paper. It creates air pockets that trap air efficiently. Cellulose can only be blown in with a special machine and can’t be applied to specific small spaces.
Fiberglass has a lower R-value rating but can serve as a good alternative for homes in climates with fewer temperature extremes. It is also the easier type to install and better suited for DIYers, because it can be purchased in rolls of batting, which you uncoil between joists. You have to cut and separate it to fit. This method isn’t the preferred application for attics, however, because air can escape between the gaps. One of the better alternatives is loose-fill fiberglass, which, like loose-fill cellulose, needs to be blown in.
If you decide to DIY your blown-in cellulose insulation, make sure to follow all of the necessary prep work, safety precautions, and guidelines for your selected method and your area of the country. You may want to have a professional first seal up any leaks for you with foam. You can find blow-in cellulose insulation at most home centers, many of which provide the blower for free if you buy a certain number of bags.
No matter which insulation product you choose, research the recommended attic R-value recommended by the U.S. Department of Energy for your area. “R49 is the recommended R-value in Iowa, which means about 18 inches of cellulose for attics here,” Webb says. “When I inspect an attic, it’s pretty rare for me to actually see that much.” Depending on where you live, your attic’s R-value could range from R30 to R60. You can use this guide to determine the R-value for your area.
You can buy insulation rated for different R-values. If the specific product you purchase isn’t the R-value you need, remember that R-value is cumulative: You can buy amounts of the product that can add to layers to achieve the desired R-value.
How do I know which insulation is best for me?
Before you choose your attic insulation product, you should consider
- Your budget
- Your DIY skills and whether you want to DIY or hire a professional
- The R-value needed for your area of the country
- Any guidelines or permits needed for your area of the country
- Safety concerns
- Specific features you want to focus on for your project, whether that’s environmental sustainability, the comfort of your home, reduction of heating and cooling bills, noise reduction, or other considerations
What preparation is needed before I insulate?
Before you install new attic insulation, consider hiring a professional to inspect existing insulation. If that has evidence of water damage, mold, pest infestation, or asbestos, have it removed by a professional who’s certified to handle hazardous materials.
Before blowing insulation into an attic, you should seal air leaks and drafts around windows with weather stripping or window/door sealant. Pipes, wires, exhaust fans, and ducts should be treated with fire-inhibiting foam insulation. You may want to engage a professional for this as well.
in addition, a professional can examine your existing insulation to determine whether it contains asbestos, which may be present in older homes that haven't been insulated recently. Asbestos can be harmful to health, but removing it yourself can exacerbate the hazard. Removal definitely needs to be done by professionals.
Why Trust the Spruce?
Missy Keenan is a freelance writer with more than two decades’ experience as a journalist and communications professional. Missy has a special interest in all things home, garden, and sustainability and has written hundreds of articles for publications including Do It Yourself magazine, Glamour magazine, USA Today, The Des Moines Register, DSM magazine, and Iowa Gardening. For this story, Missy spent hours consulting experts, combing through product reviews, and inspecting the attic of her own historic home along with a local insulation expert. (Verdict: Her attic needs more insulation!)