Spray-Applied
Closed-Cell Spray Foam Insulation
Complete guide to closed-cell spray foam insulation: R-value, installed cost, pros, cons, and best applications.
Key Specifications
6–7
R-Value per Inch
$1.50–$3.00
Material Cost/sqft
$2.50–$4.50
Installed Cost/sqft
10"
Depth for R-60
Cost Analysis (1,200 sq ft Attic)
| Option | Low Estimate | High Estimate |
|---|---|---|
| Material only (DIY) | $1,800 | $3,600 |
| Professionally installed | $3,000 | $5,400 |
*Estimates for a full install to Climate Zone 5 R-60 depth. Use the calculator for your specific situation.
+ Pros
- ✓Highest R-value per inch (6.0–7.0)
- ✓Acts as both insulation and vapor barrier
- ✓Adds structural rigidity to roof sheathing
- ✓Completely waterproof — can be used in wet areas
− Cons
- ✗Most expensive insulation option per square foot
- ✗Must be professionally installed
- ✗Off-gasses during curing — area must be vacated
- ✗Cannot be recycled or removed easily
Best Applications
- →Tight spaces where maximum R-value per inch is critical
- →Unvented roof assemblies in mixed-humid climates
- →Crawl spaces with moisture issues
- →Homes where budget is not the primary concern
Comparing Insulation Types
Closed-Cell Spray Foam is a spray-applied insulation. With R-6–7 per inch, it offers among the highest R-values per inch available, ideal for space-constrained applications.
View full insulation type comparison →Explore Other Insulation Types
Is Closed-Cell Spray Foam Right for Your Attic?
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