Spray Foam Insulation vs. Blown-In Insulation: Cost, R-Value & Pros & Cons
Is the higher cost of spray foam insulation worth the investment compared to blown-in insulation? While spray foam typically ranges from $0.75 to $4.50 per square foot and blown-in insulation ranges from $0.40 to $2.50 per square foot, the total cost comparison involves much more than just the initial price. In this article, we’ll break down the cost of blown-in insulation versus spray foam insulation, compare R-values, and discuss the long-term benefits of each.
What is Blown-In Insulation?
Blown-in insulation is a loose-fill material, typically made from cellulose, fiberglass, or mineral wool, that is blown into spaces using a specialized blower machine. This type of insulation is particularly effective for covering large areas like attics, as it can conform to irregular spaces and fill cavities with ease. One of its primary benefits is its eco-friendliness, especially cellulose, which is often made from recycled paper products. Additionally, blown-in insulation offers a cost-effective solution for homeowners seeking to improve energy efficiency in existing homes.
What is Spray Foam Insulation?
Spray foam insulation is a modern solution applied as a liquid that rapidly expands into a solid, continuous insulating layer. Its key advantage lies in its ability to create a superior airtight seal by expanding into every gap and crack. This process results in exceptional thermal performance (high R-value) and moisture resistance, making it ideal for areas requiring maximum energy efficiency. Closed-cell spray foam insulation, with its higher density and R-value, is particularly effective in extreme climates and spaces prone to moisture.
Cost Comparison: Spray Foam vs Blown-In Insulation
The cost of insulation can vary significantly depending on the type chosen.
- Closed-cell spray foam: $0.75 - $4.50 per square foot
- Open-cell spray foam: $0.55 - $2.50 per square foot
- Blown-in insulation: $0.40 - $2.50 per square foot
Key Takeaway: While spray foam has a higher initial cost, it provides better long-term energy savings compared to blown-in insulation.
R-Value Comparison: Spray Foam vs Blown-In Insulation
R-value measures an insulation material's ability to resist heat flow. Higher R-values signify better insulation.
- Closed-cell spray foam has an R-value of 5.6 to 8.0 per inch.
- Open-cell spray foam has an R-value of 3.5 to 3.8 per inch.
- Blown-in insulation typically offers an R-value of 2.2 to 3.8 per inch.
Key Takeaway: Spray foam, especially closed-cell, provides the best thermal resistance, while blown-in insulation has a lower R-value.
Installation Process: Spray Foam vs Blown-In Insulation
The installation process for spray foam and blown-in insulation varies significantly in terms of complexity and required tools.
Spray Foam Insulation:
- Requires specialized equipment (spray gun).
- Expands to fill gaps, creating an airtight seal.
- Professional installation is recommended due to the complexity.
To better understand the spray foam insulation installation process and see how it’s done, watch this helpful video:
Blown-In Insulation:
- Uses a blower machine to distribute loose-fill materials like cellulose or fiberglass.
- Easier for DIY projects and ideal for large, open areas like attics.
Key Takeaway: Spray foam insulation requires professional installation for best results, while blown-in insulation is more DIY-friendly and suitable for large spaces.
Environmental Impact: Spray Foam vs Blown-In Insulation
When considering insulation options, it's important to also evaluate their environmental impact.
Blown-In Insulation (Cellulose or Fiberglass):
- Eco-friendly: Made from recycled materials.
- Lower carbon footprint during production.
- Non-toxic fire retardants for safety.
Spray Foam Insulation:
- Higher environmental impact due to fossil fuels used in production.
- Can release volatile organic compounds (VOCs) during installation.
Key Takeaway: Blown-in insulation is more eco-friendly, especially cellulose, which is made from recycled paper products.
Long-Term Durability & Maintenance: Spray Foam vs Blown-In Insulation
The long-term durability and maintenance requirements of insulation materials play a crucial role in the overall cost-effectiveness of your investment.
Spray Foam Insulation:
- Lifespan: 50+ years (Closed-cell).
- Requires minimal maintenance.
- Very durable and resistant to moisture and air leaks.
Blown-In Insulation:
- Lifespan: 15 - 30 years.
- May require periodic maintenance due to settling over time.
- Not as durable in high-moisture areas.
Key Takeaway: Spray foam insulation offers greater durability and requires less maintenance than blown-in insulation, especially in high-moisture environments.
Energy Efficiency & Savings with Spray Foam vs Blown-In Insulation
Energy efficiency is one of the most important factors to consider when choosing insulation. Let’s compare how spray foam and blown-in insulation stack up in terms of energy savings.
Spray Foam Insulation:
- Up to 40% energy savings due to its superior air sealing.
- Ideal for homes in extreme climates.
- Moisture resistance helps reduce heat loss.
Blown-In Insulation:
- Up to 25% energy savings.
- More cost-effective but less efficient at preventing air leaks.
Key Takeaway: Spray foam insulation offers greater energy savings and air sealing benefits, especially in extreme climates, while blown-in insulation is a more budget-friendly option with moderate savings.
Key Comparison: Spray Foam vs Blown-In Insulation
To summarize the key differences between spray foam insulation and blown-in insulation, here is a quick comparison that highlights the main features to consider when making your decision.
|
Feature |
Spray Foam Insulation |
Blown-In Insulation |
|
Cost (per square foot) |
$0.75 - $4.50 (Closed-cell) / $0.55 - $2.50 (Open-cell) |
$0.40 - $2.50 |
|
Energy Savings |
Up to 40% savings |
Up to 25% savings |
|
R-Value (per inch) |
5.6 - 8.0 (Closed-cell) / 3.5 - 3.8 (Open-cell) |
2.2 - 3.8 |
|
Air Sealing |
Excellent |
Moderate |
|
Moisture Resistance |
Excellent |
Limited |
|
Durability |
50+ years (Closed-cell) |
15 - 30 years |
|
Maintenance |
Minimal |
May require top-ups over time |
|
Installation |
Requires professional installation |
DIY-friendly |
|
Eco-Friendliness |
Lower due to fossil fuel use, may release VOCs |
Higher due to recycled materials |
Ideal Applications: Spray Foam vs Blown-In Insulation
Each insulation type has its own unique set of applications that make it suitable for specific needs. Let’s explore where spray foam insulation and blown-in insulation perform best.
Spray Foam Insulation:
- Best for irregular spaces and high moisture exposure (e.g., basements, crawl spaces).
- Expands to fill gaps, providing superior air sealing.
- Recommended for new constructions or areas where airtight seals are critical.
Blown-In Insulation:
- Ideal for large areas like attics and existing wall cavities.
- Eco-friendly due to its recycled material composition.
- Great for upgrades in existing homes with minimal disruption.
Key Takeaway: Spray foam is ideal for areas requiring maximum energy efficiency and moisture resistance, while blown-in insulation is best for large, open spaces and eco-conscious projects.
The Final Verdict: Which Insulation Is Right for You?
As we've compared them, the choice between spray foam and blown-in insulation boils down to a key trade-off: upfront cost and eco-friendliness versus long-term performance and durability. Blown-in insulation offers a solid, budget-friendly, and environmentally conscious solution, particularly for straightforward applications like open attics.
On the other hand, spray foam stands as the premium option for homeowners seeking the highest level of energy efficiency. Its superior R-value, unparalleled air-sealing capabilities, and exceptional longevity represent a significant long-term investment. While the initial cost is higher, the potential for up to 40% in energy savings ensures a powerful return over the life of your home.
Two Scenarios to Guide Your Decision:
- If your top priorities are maximum energy savings, a flawless airtight seal, and decades of durability, then spray foam insulation is the unmatched investment for your project.
- If you are working with a tighter budget, value eco-friendly materials, and need effective coverage for a standard space, blown-in insulation is a sensible and reliable choice.
If high-performance insulation aligns with your home improvement goals, the next step is to find the right materials for the job.
[Explore Our Spray Foam Insulation Kits]
FAQ
Is blown-in insulation better than spray foam?
Blown-in insulation offers environmentally friendly options and is easier to install, whereas spray foam provides superior thermal resistance and air sealing capabilities, ideal for irregular spaces and high moisture areas like basements.
Spray foam insulation vs blown-in: Cost comparison?
Spray foam insulation, especially closed-cell, has a higher initial cost ($0.75–$4.50 per sq ft) compared to blown-in ($0.40 - $2.50 per sq ft), but offers up to 40% energy savings, offsetting its cost over time.
For a more detailed breakdown of spray foam insulation costs, check out our blog post on “How Much Does Spray Foam Insulation Cost in 2025?”.
Spray foam vs blown-in insulation R-value comparison?
Closed-cell spray foam provides an R-value of 5.6-8.0 per inch, offering superior insulation compared to blown-in, which has an R-value of 2.2-3.8 per inch, impacting energy efficiency significantly.
To learn more about the R-value of spray foam insulation and its importance for energy efficiency, check out our blog post on “What Is the R-Value of Spray Foam Insulation and Why Does It Matter?”.
What is the advantage of spray foam insulation?
The main advantage of spray foam insulation is its ability to create an airtight seal, improving energy efficiency and thermal performance. It also offers moisture resistance, making it ideal for areas prone to humidity, and has a long lifespan with minimal maintenance.
What is the disadvantage of spray foam insulation?
Spray foam can release volatile organic compounds (VOCs) and requires professional installation for optimal effectiveness, raising both environmental concerns and upfront costs compared to other insulation methods.
Is spray foam or blown-in insulation better for an attic?
Spray foam excels in air sealing and thermal resistance, making it suitable for attics with irregular spaces. Blown-in is preferable for larger areas and eco-conscious projects due to its environmentally friendly nature.
Spray foam vs blown cellulose: Which is more eco-friendly?
Blown cellulose insulation, made from recycled materials, offers an eco-friendly alternative, while spray foam is less sustainable due to its production using fossil fuels and potential VOC emissions.