Exploring Open Cell vs Closed Cell Insulation

At MPI Foam, we recognize that choosing the right insulation for your property is a significant decision—one that goes beyond comfort, impacting your long-term investment. We want to ensure you understand the difference between closed-cell and open-cell spray foam insulation so that you can make an informed choice that aligns with your specific needs.


The Cellular Divide: Open Cell vs Closed Cell Insulation

The terms “open-cell” and “closed-cell” refer to the fundamental structural differences in these foam types—differences that define their unique properties.

Open-Cell Foam Insulation: Open-cell insulation retains intentionally open cells, yielding a softer and more flexible material. This open structure makes it ideal for particular applications.

Closed-Cell Foam Insulation: In contrast, closed-cell insulation consists of completely sealed cells, creating a dense, rigid, and stable foam with specific advantages tailored to particular requirements.



Closed Cell Foam Insulation: Closed cell insulation boasts significantly higher density, often exceeding 1.75 pounds per cubic foot. This dense composition contributes to its structural stability and durability.

Open Cell Foam Insulation: Most open cell insulation registers a density of approximately 0.5 pounds per cubic foot, reflecting its softer and more pliable nature.


R-Value: The Insulation Benchmark

The R-value measures a foam’s resistance to heat flow, a critical factor in evaluating its insulating capabilities. There is a difference between closed-cell and open-cell spray foam insulation.

Closed Cell Foam Insulation R-Value: With an R-value typically around 6.0 per inch, closed cell foam excels in insulating against heat transfer. Specialized closed-cell foams can achieve remarkable ratings approaching 7 per inch. This high closed-cell foam insulation r value makes closed-cell insulation a premier choice for maintaining consistent temperatures in structures.

Open Cell Foam Insulation R-Value: Open cell insulation generally delivers an R-value of around 3.5 per inch. While respectable, this R-value is notably lower than that of closed-cell foams, which may limit its suitability in extreme temperature conditions.



Understanding how these foams expand during application is crucial for proper use.

Closed-Cell Foam Insulation: When sprayed, closed-cell insulation expands to a thickness of approximately 1 inch. With each inch offering an impressive R-value of 7, multiple applications can be layered to achieve higher total R-values, enhancing insulation effectiveness.

Open-Cell Foam Insulation: In contrast, open-cell insulation expands to a thickness of about 3 inches upon application, allowing for only one application in most standard walls. While this provides adequate insulation for many scenarios, it may not offer the same level of insulation versatility as closed-cell foam.



Closed-Cell Foam Insulation: Since closed-cell foam insulation can achieve 2x the R-value of an open cell inside a standard wall, it’s the best choice for insulation where space is an issue. Its rigid nature adds to the structural integrity of a building. The closed cells also act as a vapor barrier to prevent moisture from getting inside your home and the foam itself will remain unharmed. Ideal for extreme weather temperatures.

Open-Cell Foam Insulation: Since open-cell foam insulation expands so much after being applied, it can insulate hard-to-reach nooks and crannies. It’s excellent for soundproofing and is more affordable than the spray foam insulation closed cell.


Location: Difference Between Closed Cell and Open Cell Spray Foam Insulation


Attic Insulation

When it comes to attic insulation, you have choices that can significantly impact your home’s energy efficiency and comfort.

Closed-Cell Foam Insulation for Attic:

  • Impressive Thermal Performance: Closed cell insulation delivers top-notch thermal resistance, keeping your attic comfortable.
  • Moisture Management: Guards against moisture, mold, and mildew.
  • Enhanced Durability: Adds structural integrity to your attic and roof.

Open-Cell Foam Insulation for Attic:

  • Moderate Climate Comfort: Ideal for maintaining indoor comfort in moderate climates.
  • Air Exchange Benefits: Allows for controlled air exchange, suited for milder regions.
  • Budget-Friendly: Open cell insulation offers a cost-effective solution for attic insulation.


Crawlspace Insulation

When it comes to crawlspace insulation, making the right choice is crucial for maintaining a comfortable and energy-efficient home.

Closed-Cell Foam Insulation for Crawlspace:

  • Moderate Climate Comfort: Offers an economical solution for specific attic needs.
  • Air Exchange Benefits: Offers an economical solution for specific attic needs.
  • Budget-Friendly: Offers an economical crawlspace insulation solution.

Open-Cell Foam Insulation for Crawlspace:

  • Cost Effective: Open cell insulation provides adequate crawlspace insulation at a cost-effective price
  • Ventilation-Friendly: It allows controlled moisture and air exchange, ideal for specific crawl space conditions.


Garage Insulation

When it comes to garage insulation, it’s not just about keeping your vehicles and belongings safe; it’s also about enhancing your living spaces and energy efficiency.

Closed-Cell Foam Insulation for Garage:

  • Noise Reduction: Ideal for reducing noise for garage ceilings.
  • Temperature Consistency: Maintains stable temperatures within the garage.
  • Long-Term Reliability: Offers a durable garage insulation solution.

Open-Cell Foam Insulation for Garage:

  • Noise Control: Effectively reduces noise for garage ceilings and walls.
  • Ventilation-Friendly: Suitable for garages requiring ventilation.
  • Cost-Effective: Budget-friendly option for garage insulation, especially for storage.


Why MPI Foam?

  1. Informed Decision: At MPI Foam, we believe that making an informed decision is crucial. We provide detailed information and expert guidance to ensure you choose the right spray foam insulation for your needs.
  2. Professional Excellence: Our experienced team ensures the highest quality of spray insulation installation, delivering results that exceed expectations.
  3. Long-Term Savings: Our open-cell insulation or closed-cell insulation not only enhances comfort but also leads to significant energy savings, making your investment worthwhile.


In conclusion, when making your decision, the difference between closed-cell and open-cell spray foam insulation relies primarily on what you want to get out of that space.

At MPI Foam, we are dedicated to delivering spray foam insulation that lasts. We encourage you to reach out to us to discuss your insulation project. Let’s work together to ensure your property enjoys the benefits of the right insulation, providing comfort, energy efficiency, and enduring performance.

Get started with an MPI Foam specialist by calling 844-MPI-FOAM (844-674-6262) or request a free quote for MPI Foam’s spray foam insulation today!

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