Fiberglass Attic Insulation

One of the most popular home-improvement projects for both DIYers and professional contractors. Adding insulation to the attic is an easy and proven way to increase home comfort and decrease energy costs. It also can help increase the value of your home. Even though insulation is hidden, it shouldn't be forgotten.
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Key Benefits
Reduced Noise
Reduce room-to-room sound transmission
Save Money
Save on your home’s heating and cooling bills
Boosted Resale Value
A home improvement project that can pay back more than invested
Year-Round Comfort
Maintain indoor temperatures in the winter and the summer
Getting Started

Before you jump into your attic insulation project, there's some key information to take into account. One of the biggest benefits of insulating your attic is thermal performance. It can help enhance the comfort of your home. So how do you make sure you’re getting the maximum benefits? Install insulation with the proper R-value

How Do You Figure Out R-Value?

R-value refers to the insulation’s ability to resist heat flow. The greater the R-value the greater the insulating performance. R-value requirements are different based on your location. Colder climates will typically require a higher R-value for even greater thermal resistance. Use the energy code map to help determine R-value for your region. Learn more about insulation r-value.

Installing Fiberglass Attic Insulation 

First time adding insulation to an attic? Don’t sweat it. We’ll walk you through the steps to help you find the right type of fiberglass attic insulation and the right amount. First, you'll need to determine your R-value. If it’s a new building, simply reference the energy code map.

If the attic is already insulated, you’ll want to check the current R-value. It can be located on a card left by the previous installer, printed on the attic insulation or you can measure it yourself. Take your measuring tape and measure how deep it is. 
  • For loose fill, such as EcoFill, multiply the depth by a minimum of R-2.67 per inch.
  • For batts, such as EcoBatt, multiply the depth by a minimum of R-3 per inch.

Once determined, subtract the current R-value from your desired R-value, to get the R-value you need to add.

Determining Your Attic Insulation Needs


  1. Calculate the square footage of the attic you’re insulating. Measure the length and width of the attic, then multiply those numbers to get the total square footage:

    Length X Width = Total Square Footage

  2. Determine what kind of fiberglass attic insulation you want to use — batts, rolls or loose fill. Keep in mind that batts should never be installed over blown-in insulation.
  3. Once you know the product you want, you can estimate the amount you’ll need. Divide attic’s square footage by the square footage in each package.

    Attic Sq. Ft. ÷ Package Sq. Footage = How Many Packages to Buy

    Be sure to check the R-value on the package to ensure you’re getting the right density.
  4. When you install, avoid blocking air flow from soffit vents. Note that you may need to install baffles to channel the air flow above insulation.

Attic Insulation Products
Ready to install? Browse our full line of fiberglass attic insulation and more to find the right product for you.
Jet Stream® Ultra Blowing Wool
Our flagship product providing excellent thermal performance for new construction and existing buildings.
Bag Net Weight
32 lbs
Jet Stream® Max Premium Blowing Wool (Canada Only)
Premium insulation provides excellent thermal performance for new construction and existing buildings.
Bag Net Weight
14.5 kg
EcoFill® Wx Blowing Wool
Designed for weatherizing and retrofitting existing buildings or new construction, providing consistent thermal performance.
Bag Net Weight
28.6 lbs
EcoRoll® Insulation
Quality thermal and acoustical insulation with ECOSE® Technology for attics, floors, walls, ceilings and more.
3.5" - 10"
R-11 - R-30
15" and 23"
EcoBatt® Insulation
Quality engineered thermal and acoustical fiberglass batt insulation with innovative ECOSE® technology is ideal for floors, walls, ceilings and attics.
2.5" - 13.75"
R-8 - R-49
11" - 24"
ECOSEAL™ Plus Sealant
Water-based elastomeric sealant that fills joints, gaps and penetrations to prevent air infiltration.
Shelf Life
18 months
2400 ft/bucket
Full Truckload Only
How to Choose the Right Insulation
Fiberglass Insulation
The smart choice to make spaces more comfortable and energy efficient.
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The ability to resist heat flow — insulation's thermal resistance.
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Thermal Properties
Ability to enhance a thermal enclosure for comfort and efficiency.
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Insulating For Sound
Sound absorption characteristics, helping reduce noise transmission.
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