The cost to insulate an attic in 2025 generally ranges from about $1 to $7 per square foot, depending on the insulation material, attic size, and labor involved.
Typical Cost Ranges
- Average total cost for insulating an attic is around $1,500 to $6,000 for a typical attic size, with some estimates averaging about $2,100 to $2,400 including professional installation
- For smaller attics (e.g., 500 sq. ft.), costs can be between $530 and $3,000 , while larger attics (1,500 sq. ft.) may cost $1,590 to $9,000
- Per square foot, costs typically range:
- Low end: $0.50 to $1.50 (reflective insulation)
- Mid-range: $1 to $3 (fiberglass, cellulose)
- High end: $4 to $7 (spray foam, structural insulated panels)
Cost Factors
- Material type : Fiberglass is cost-effective ($0.90–$1.80/sq ft), cellulose is eco-friendly and moderately priced ($1.20–$3.20/sq ft), spray foam offers superior insulation but costs more ($1.50–$5.00/sq ft), and rigid foam is the most expensive ($3.00–$5.50/sq ft)
- Attic size : Larger attics require more material and labor, increasing total cost.
- Labor and installation complexity : Professional installation adds to the cost, typically included in the $1 to $6 per square foot estimate.
- Removal of old insulation : If needed, removal can add to the total expense, sometimes equaling the cost of new insulation
- Regional pricing and supply chain factors : Costs have risen post-pandemic due to supply disruptions and increased demand
Summary Table of Average Costs per Square Foot by Insulation Type
Insulation Type| Cost per Sq. Ft.| Typical R-Value per Inch| Notes
---|---|---|---
Reflective| $0.50 – $1.50| N/A| Best for warm climates
Fiberglass| $0.90 – $1.80| R-2.9 to R-3.8| Budget-friendly option
Cellulose| $1.20 – $3.20| R-3.2 to R-3.8| Eco-friendly, good for retrofits
Spray Foam (open/closed cell)| $1.50 – $5.00| R-6.5 (closed cell)| Higher
initial cost, better sealing
Rigid Foam| $3.00 – $5.50| R-4 to R-6.5| Durable, moisture resistant
In conclusion, insulating an attic typically costs between $1,500 and $6,000 depending on size and materials, with a per square foot cost ranging from about $1 to $6 for professional installation. Choosing the right insulation depends on your budget, climate, and energy efficiency goals
