How Much Does Spray Foam Insulation Cost?

What Is Spray Foam Insulation and How Does It Work?

Spray foam insulation is an expanding foam material that fills and seals gaps in your home's structure. There are two main types of insulation:

• Open-cell foam (softer, flexible, and breathable)
  
• Closed-cell spray foam (denser, moisture-resistant, and high R-value)
  

This insulation material is often used in attics, wall insulation, basements, and garages, where it delivers thermal insulation and moisture resistance far beyond traditional insulation.

How Much Does Spray Foam Insulation Cost Per Square Foot?

The spray foam insulation cost per square foot depends on several variables including foam type, project size, and labor rates. Here’s a typical cost range:

The spray foam cost per board foot ranges from $1.25 to $2.50. This can increase depending on installation cost, prep work, and square footage.

Closed Cell vs. Open Cell Spray Foam: What’s the Cost Difference?

When evaluating the cost of spray foam, choosing the right type of spray foam is critical.

• Open-cell foam is cheaper and less dense, making it ideal for interiors.
  
• Closed-cell spray foam insulation costs more but offers a higher insulation R-value and acts as a vapor barrier.
  

For projects like attic insulation, closed-cell spray foam is often worth the higher total cost due to energy savings and durability.

Spray Foam Insulation Cost for Attics

The cost to insulate an attic with spray foam depends on size, existing insulation, and complexity:

• Small attic (500 sq ft): $1,000 – $2,500
  
• Medium attic (1,000 sq ft): $2,000 – $5,000
  
• Large attic (2,000+ sq ft): $4,000 – $8,000
  

Attic spray foam insulation can significantly reduce your heating and cooling bills. The insulation cost per sq ft may rise due to old insulation removal, steep rooflines, or difficult access.

Average Cost to Insulate a Garage with Spray Foam

The cost to insulate a garage with spray foam varies depending on:

• Size of the garage
  
• Closed-cell spray foam vs. open-cell
  
• Ease of install insulation
  

Average costs:

• Attached garage: $1,000 – $3,500
  
• Detached garage: $1,500 – $4,000
  

For garages used as workshops or gyms, closed-cell spray foam insulation provides structural support, air sealing, and comfort.

Cost Factors That Affect Spray Foam Installation

Many cost factors affect the price of spray foam insulation, including:

• Square footage of the area
  
• Type of insulation used (closed vs. open cell)
  
• Thickness needed per inch
  
• Labor and prep time
  
• Old insulation removal
  
• Roof access or crawlspace difficulty
  

Always get multiple quotes to compare the installation cost and scope of work.

DIY Spray Foam Insulation vs. Professional Installation

Considering DIY spray foam installation? Here's how it compares:

• DIY spray foam insulation cost: $300–$600 per kit (covers ~200 sq ft @ 1” thick)
  
• Professional spray foam installation: $1.50–$3.50 per sq ft
  

While DIY kits may seem budget-friendly, incorrect application risks poor performance. In large areas like attics, professional spray foam ensures code compliance and full coverage.

Spray Foam Insulation Kits: Are They Worth It?

Spray foam insulation kits are ideal for small repairs or isolated jobs. Features:

• Available in both open-cell and closed-cell
  
• Cost: $3–$5 per board foot
  
• Coverage: limited and labor-intensive
  

For anything larger than a small wall or crawlspace, DIY kits are not cost-effective.

Benefits of Professional Spray Foam Insulation Beyond Cost

While spray foam insulation typically ranges higher than fiberglass insulation or blown-in insulation, it offers major benefits:

• Foam provides superior thermal insulation
  
• Combines insulation and air sealing
  
• High insulation R-value per inch
  
• Reduced HVAC usage → lower energy bills
  
• Long lifespan doesn’t sag or degrade
  
• Strong resistance to moisture and mold
  

Spray foam insulation can save thousands over time, making it a smart upgrade for any homeowner.

How to Plan Your Spray Foam Insulation Project

To plan your insulation project effectively:

1. Decide the best insulation type
   
2. Measure square footage and required R-value
   
3. Get multiple quotes from professional spray foam contractors
   
4. Explore insulation offers and federal tax credits
   
5. Schedule installation and prepare your attic or garage
   

Choosing the right insulation upfront can help you save on both material and energy bills long-term.

Summary: Key Takeaways on the Cost of Spray Foam Insulation

• Spray foam insulation cost ranges from $0.45 to $2.00 per sq ft, depending on the foam type
  
• Closed cell spray foam offers better performance but costs more
  
• Attic insulation averages $2,000 to $8,000 depending on size
  
• Garage insulation ranges between $1,000 and $4,000
  
• DIY kits may work for small areas, but professionals are better for full installations
  
• Installing spray foam insulation can reduce HVAC load and boost comfort
  
• Always consider cost factors like prep, area size, and labor
  
• The price of spray foam insulation may be higher up front, but it offers a strong ROI
  
• Spray foam insulation is often more durable and effective than traditional insulation
  
• Plan carefully to add insulation where it matters most and maximize savings
  

Contact Green Attic Insulation today to explore affordable, high-performance home insulation options customized to your needs and find out exactly how much does it cost to insulate your attic, garage, or entire home.