Loose-Fill (Blown-In)
Blown-in Fiberglass Insulation
Complete guide to blown-in fiberglass insulation: R-value, installed cost, pros, cons, and best applications.
Key Specifications
2.2–2.7
R-Value per Inch
$0.40–$0.65
Material Cost/sqft
$1.00–$1.50
Installed Cost/sqft
25"
Depth for R-60
Cost Analysis (1,200 sq ft Attic)
| Option | Low Estimate | High Estimate |
|---|---|---|
| Material only (DIY) | $480 | $780 |
| Professionally installed | $1,200 | $1,800 |
*Estimates for a full install to Climate Zone 5 R-60 depth. Use the calculator for your specific situation.
+ Pros
- ✓Inexpensive material cost
- ✓Widely available at home improvement stores
- ✓Non-combustible and does not absorb moisture
- ✓Suitable for DIY installation with rental blower
- ✓Settles less than cellulose over time
− Cons
- ✗Lower R-value per inch than cellulose
- ✗Lightweight — can shift in windy attics
- ✗Fibers can irritate skin and lungs during install
- ✗Requires more depth to hit high R-value targets
Best Applications
- →Budget-conscious homeowners
- →Attics with adequate depth for added insulation
- →DIY projects with blower rental
- →Supplementing existing batt insulation
Comparing Insulation Types
Blown-in Fiberglass is a loose-fill (blown-in) insulation. With R-2.2–2.7 per inch, it is suited to applications where depth is not a constraint.
View full insulation type comparison →Explore Other Insulation Types
Is Blown-in Fiberglass Right for Your Attic?
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