Best Attic Insulation: Top Picks from The Home Depot
A properly insulated attic can help improve energy efficiency, indoor comfort, and temperature control. But choosing the right insulation depends on your attic design, existing insulation, climate zone, available space, and the R-value you need.
Here are some of the best attic insulation options currently listed at The Home Depot.
🥇 1. Knauf Insulation R-30 Unfaced Fiberglass Roll — Best Overall
Knauf Insulation R-30 Unfaced Fiberglass Roll
Model # 613430
- R-value: R-30
- Size: 15 in. x 22 ft.
- Designed for attic and floor applications
- Class A fire-rated
- Approx. price: $43–$46 per roll
- Approx. coverage: 28 sq. ft.
This is a practical choice for homeowners who want roll insulation that is relatively easy to install between attic framing members.
Best for: Standard attic insulation projects and DIY installation. The Home Depot
🏠 2. Knauf R-38 Kraft-Faced Fiberglass Batts — Best for Higher R-Value
Knauf Insulation R-38 Kraft Faced Fiberglass Batts
- R-value: R-38
- Available in different widths
- Designed for floor, attic and ceiling applications
- Sound-reducing
- Approx. price: $116–$127 per bag, depending on size
R-38 provides more thermal resistance than R-30, making it an attractive option where the available cavity depth and local energy requirements allow it.
Best for: Homeowners looking for higher attic insulation performance. The Home Depot
🔥 3. Knauf EcoFill Blown-In Fiberglass — Best for Irregular Attics
Knauf Insulation Class A Fire-Rated Blown-In Fiberglass EcoFill
- R-value varies according to installed depth
- Loose-fill fiberglass
- Designed specifically for attic applications
- Sound reducing
- Class A fire-rated
- Approx. price: $54 per 28.6-lb. bag
- Approx. coverage: 51¢/sq. ft. at the listed configuration
Blown-in insulation is particularly useful where an attic has irregular areas, obstructions, wiring, or difficult-to-reach spaces.
Best for: Existing attics and areas that are difficult to insulate with standard batts. The Home Depot
🌸 4. Owens Corning R-38 Unfaced Fiberglass Batt — Best Brand Option
Owens Corning R-38 Unfaced Fiberglass Batt
Model # W64
- R-value: R-38
- Fiberglass batt
- Designed for attic applications
- Unfaced
- Approx. $529 per 8-bag pallet
- Approx. $1.55/sq. ft.
Owens Corning is one of the most recognizable insulation brands, and this R-38 product is a good option for homeowners who prefer a higher-R-value fiberglass batt system.
Best for: Larger attic projects and homeowners who prefer Owens Corning. The Home Depot
🌱 5. Greenfiber Cellulose Blown-In Insulation — Best Cellulose Option
Greenfiber 25-lb. Cellulose Blown-In Insulation
Model # INSSANC
- Material: Cellulose
- Approx. price: $15.97 per bag
- Approx. coverage: 33¢/sq. ft.
- Designed for blown-in or spray-applied installation
Cellulose is another popular option for attic insulation. Its loose-fill format makes it useful for covering large attic areas and filling around obstacles.
Best for: Budget-conscious attic insulation projects and loose-fill applications. The Home Depot
🏗️ 6. Johns Manville Attic Pro Fiberglass — Best for Hard-to-Reach Areas
Johns Manville Attic Pro Fiberglass Blown-In Insulation
Model # B781
This blown-in fiberglass product is designed to fill gaps, crevices and hard-to-reach spaces. Home Depot also notes that typical installation jobs can take around 4–6 hours and that a machine rental may be available with qualifying purchases. The Home Depot
Best for: Existing attics with irregular spaces and difficult areas.
Quick Comparison
| Product | Type | R-Value | Approx. Price | Best For |
|---|---|---|---|---|
| Knauf R-30 Unfaced Roll | Fiberglass Roll | R-30 | ~$43–$46 | 🥇 Overall |
| Knauf R-38 Kraft Faced | Fiberglass Batt | R-38 | ~$116–$127 | Higher R-value |
| Knauf EcoFill | Blown-in Fiberglass | Variable | ~$54/bag | Irregular attics |
| Owens Corning R-38 | Fiberglass Batt | R-38 | ~$529/pallet | Large projects |
| Greenfiber Cellulose | Blown-in Cellulose | Variable | ~$16/bag | Budget option |
| Johns Manville Attic Pro | Blown-in Fiberglass | Variable | Varies | Hard-to-reach areas |
Prices are approximate and may change based on location, quantity, and availability. The Home Depot
Fiberglass vs. Blown-In Insulation
Fiberglass Batts & Rolls
Advantages:
- Relatively easy to install
- Predictable dimensions
- Good for regular joist spacing
- Available in R-30 and R-38 options
- Good DIY option
Best when: Your attic has accessible, regularly spaced framing.
Blown-In Insulation
Advantages:
- Fills irregular spaces
- Good around obstructions
- Can be installed over existing insulation in appropriate applications
- Useful for large attic floors
Best when: Your attic has complicated framing, wiring, ducts, or difficult-to-reach areas.
Home Depot currently lists both fiberglass and cellulose blown-in insulation, including Greenfiber, Knauf, and Owens Corning products. The Home Depot
What R-Value Should You Choose?
The required attic insulation level depends on your climate zone and building design. Don't simply choose the highest R-value because it sounds better.
For example, Home Depot's Greenfiber installation guide gives recommended ranges for an uninsulated attic from R-30 through R-60 depending on climate zone. The Home Depot
For a new construction or permit project, always verify the required insulation level against the applicable energy code and local jurisdiction requirements.
Important Attic Insulation Tips
Before installing insulation:
✅ Seal major air leaks around the attic access, penetrations and top plates.
✅ Make sure the attic has appropriate ventilation where required.
✅ Don't block soffit ventilation with insulation.
✅ Keep insulation away from heat-producing fixtures unless the fixture is specifically rated for the installation.
✅ Check for moisture or roof leaks before insulating.
✅ Don't compress fiberglass insulation unnecessarily.
✅ Use the manufacturer's installation instructions.
If you're adding insulation to an existing attic, fixing air leakage and moisture problems first is important.
🏆 Which Attic Insulation Is Best?
For a straightforward attic project, Knauf R-30 Unfaced Fiberglass Roll is a practical overall choice.
If you need more thermal resistance and have enough space, R-38 fiberglass batts are worth considering.
For an attic with lots of irregular areas and obstructions, blown-in fiberglass or cellulose can provide better coverage.
🛒 Shop Attic Insulation at The Home Depot
The Home Depot – Attic Insulation
The Home Depot currently has a dedicated attic insulation section with fiberglass rolls, batts, blown-in insulation, rigid foam products and other options. The Home Depot