Spray Foam vs Blown-In Insulation: Which Insulation is Best for Your Home?
Choosing the right insulation for your home is one of the most important decisions when it comes to energy efficiency, comfort, and cost savings. In this post, we will compare two common insulation types—spray foam and blown-in insulation—helping you understand which option might be best suited for your needs. We’ll dive into the benefits, differences, costs, and R-values, giving homeowners a clear idea of what to expect when selecting insulation for their attic or other parts of the home.
What Is Spray Foam Insulation?
Spray foam insulation is a versatile and highly effective insulation method that involves spraying a liquid foam into walls, ceilings, or other surfaces where it expands and hardens into a dense, solid barrier. This type of insulation offers both open-cell foam and closed-cell foam options. Open-cell foam is less dense and better suited for interior applications, while closed-cell foam is denser, offering a higher R-value per inch and greater resistance to moisture, making it ideal for external applications like roofs and attics.
The R-value of spray foam insulation typically ranges from 5 to 7 per inch, making it one of the most efficient insulation materials available. The polyurethane foam used in spray insulation has the added advantage of sealing cracks and gaps, acting as an air barrier and preventing air leaks that can drive up energy bills.
What Is Blown-In Insulation?
Blown-in insulation, also called loose-fill insulation, involves blowing or spraying small particles of fiberglass or cellulose insulation into attics, walls, and other spaces. The particles settle into gaps and crevices, creating a thermal barrier that improves your home’s energy efficiency. Blown-in insulation is commonly used in older homes or retrofitting projects, as it can be applied without removing walls or floors.
There are two primary types of blown-in insulation:
- Blown-in fiberglass insulation: Made from fine glass fibers, this material is non-combustible and resistant to moisture.
- Blown-in cellulose insulation: Derived from recycled paper products, cellulose is an eco-friendly choice with good thermal performance.
While blown-in insulation is less expensive than spray foam, it has a lower R-value per inch, typically ranging from 2.2 to 3.8 per inch, depending on the material.
Spray Foam vs Blown-In Insulation: Which is More Energy Efficient?
When comparing the energy efficiency of spray foam and blown-in insulation, spray foam insulation comes out on top. Thanks to its superior R-value per inch (5 to 7 for spray foam vs. 2.2 to 3.8 for blown-in insulation), spray foam provides better thermal resistance, meaning your home stays warmer in winter and cooler in summer with less energy use.
Spray foam’s expanding nature also means it forms a complete air seal, minimizing the air leaks that are common with blown-in insulation. Blown-in materials like fiberglass insulation or cellulose insulation can shift over time, reducing their overall effectiveness.
By reducing energy bills by up to 50%, spray foam is often the most energy-efficient option, especially in regions with extreme temperatures.
Which Insulation Offers Better Air Sealing?
One of the most significant advantages of spray foam insulation is its ability to provide a complete air seal. The foam expands to fill even the smallest cracks and gaps, preventing unwanted air infiltration that can affect your home’s temperature stability and increase heating or cooling costs.
On the other hand, blown-in insulation can leave small gaps that allow air to move freely, particularly in hard-to-reach areas. While it can still improve your home’s energy efficiency, it doesn’t provide the same level of air sealing as spray foam. In particular, blown-in cellulose insulation might shift or settle over time, leading to gaps that reduce its overall efficiency.
Spray Foam More Expensive Than Blown-In Insulation?
Yes, spray foam insulation is typically more expensive upfront compared to blown-in insulation. The cost of spray foam ranges from $1.50 to $3.00 per square foot, depending on whether you choose open-cell or closed-cell foam, while blown-in insulation costs between $0.60 and $1.20 per square foot.
However, it’s important to consider the long-term savings. Homeowners often see a 20-50% reduction in energy bills with spray foam, which can offset the higher initial cost within just a few years. The increased durability and longer lifespan of spray foam also mean fewer repairs or replacements, making it a cost-effective choice over time.
Comparing R-Values: Spray Foam and Blown-In Insulation
The R-value measures an insulation material’s resistance to heat flow—the higher the R-value, the better the insulation’s effectiveness. Spray foam insulation generally has a higher R-value per inch (5 to 7) than blown-in insulation (2.2 to 3.8). This means you need less spray foam to achieve the same level of thermal resistance as you would with blown-in insulation.
- Open-cell spray foam: R-value of about 3.5 to 4.0 per inch
- Closed-cell spray foam: R-value of 6.5 to 7.0 per inch
- Blown-in fiberglass insulation: R-value of 2.2 to 2.7 per inch
- Blown-in cellulose insulation: R-value of 3.2 to 3.8 per inch
This higher R-value makes spray foam a better option for homeowners looking to maximize energy efficiency, especially in challenging climates.
Which Insulation is Best for Attics?
Both spray foam insulation and blown-in insulation can be used effectively in attics, but spray foam is often considered the superior option for attic insulation. Spray foam provides a complete air barrier, which is crucial for preventing heat loss and maintaining temperature control in your attic. By sealing all cracks and gaps, spray foam prevents air leakage, moisture build-up, and pest infiltration, making it ideal for attics.
On the other hand, blown-in insulation is often used in attics due to its ease of application and affordability. It’s particularly useful for filling irregularly shaped spaces, but it does not provide the same level of air sealing as spray foam. Blown-in insulation also tends to settle over time, potentially reducing its effectiveness.
Health and Safety Considerations
Both spray foam and blown-in insulation have safety considerations to keep in mind. During installation, spray foam releases chemicals that can irritate the skin, eyes, and respiratory system. Professional installation is required to minimize exposure and ensure proper ventilation during the curing process.
Blown-in insulation materials, such as fiberglass or cellulose, are generally considered safe. However, fiberglass particles can become airborne during installation, so protective gear is recommended for both installers and homeowners.
Spray Foam and Blown-In Insulation Installation
When it comes to installation, both spray foam insulation and blown-in insulation should be installed by a professional insulation installer. Spray foam, in particular, requires specialized equipment and expertise to ensure even coverage and proper curing.
Blown-in insulation, while easier to install, also benefits from professional installers, especially in large or hard-to-reach areas like attics. A skilled installer can ensure that the insulation is distributed evenly and that all gaps are properly filled, maximizing energy efficiency.
Which Insulation Is Right for Your Home?
When choosing the right insulation for your home, several factors come into play, including budget, energy efficiency goals, and the type of space you need to insulate. Spray foam is the best choice if you’re looking for superior R-value, air sealing, and moisture resistance. It’s particularly well-suited for attics, basements, and other areas where temperature control and air sealing are crucial.
On the other hand, blown-in insulation offers a more affordable option with good thermal resistance, especially in attics and walls. Cellulose insulation is an environmentally friendly choice, while fiberglass insulation is durable and moisture-resistant. If you’re insulating an existing home or need to cover a large area on a budget, blown-in insulation might be the right choice.
Spray Foam vs Blown-In Comparison Chart
| Feature | Spray Foam Insulation | Blown-In Insulation |
|---|---|---|
| R-Value per Inch | 5 to 7 (Closed-Cell) 3.5 to 4 (Open-Cell) |
2.2 to 3.8 (Fiberglass or Cellulose) |
| Air Sealing | Excellent – Provides an airtight seal | Good – Some gaps and settling possible |
| Moisture Resistance | High – Closed-cell is moisture-resistant | Moderate – Can absorb moisture (especially cellulose) |
| Material Options | Open-cell or Closed-cell Polyurethane Foam | Fiberglass or Cellulose |
| Cost | $1.50 to $3.00 per square foot | $0.60 to $1.20 per square foot |
| Installation Process | Spray application, requires professional installer | Blown-in, easier to install but still recommended for professionals |
| Durability | Up to 30 years or more | 10-20 years, with potential for settling |
| Environmental Impact | Moderate (depends on material used) | High for Cellulose (85% recycled content), Moderate for Fiberglass |
| Soundproofing | Excellent (Open-Cell) | Good |
| Best Application Areas | Attics, Walls, Crawlspaces, Basements | Attics, Walls (primarily retrofitting older homes) |
| Energy Efficiency | Reduces energy bills by up to 50% | Reduces energy bills by up to 30% |
| Time to Install | Longer – Requires proper safety and equipment | Shorter – Faster to install |
| Longevity | 30+ years | 10-20 years, with potential settling over time |
Transcend Spray Foam Solutions is Here to Help
At Transcend Spray Foam Solutions, we specialize in providing top-notch insulation services for homeowners in the Southeast United States. With over 30 years of experience, our dedicated team is here to help you find the best insulation solution that fits your needs and budget. We stand behind the quality of our services and ensure you get the most energy-efficient options for your home.
Reach out to us today, and let’s discuss how we can help make your home more comfortable and energy-efficient.
