When you’re considering insulation, the type of spray foam you choose makes a difference not just in performance, but in cost, comfort, and long-term durability. At All Foam & Insulation, LLC, we’ve worked with hundreds of Oregon homeowners and contractors, helping them understand whether closed-cell or open-cell spray foam is the better fit for their specific needs.
This guide gives you the clarity you need to make a confident, informed decision. We’ll explain what makes these two insulation types so different, how they each perform in real-world conditions, and what factors should drive your choice always through the lens of our experience and local expertise.
How Spray Foam Works and Why It Matters
Spray foam insulation expands when applied, filling gaps and sealing air leaks more completely than traditional insulation types. It’s this expansion that helps create a tighter, more energy-efficient building envelope but not all spray foam is the same.
Open-cell and closed-cell spray foams have different chemical structures, densities, and applications. Our job is to help you understand those differences clearly so you get insulation that performs exactly the way you need it to.
Open-Cell vs. Closed-Cell: What’s the Core Difference?
Open-cell foam is softer and more flexible. Its lower density makes it ideal for interior walls where sound absorption and breathability matter. Closed-cell foam is denser and acts as a moisture barrier, making it better for exterior applications and unvented attics.
Understanding Spray Foam Expansion and R-Value
Open-cell foam expands more up to 100x its liquid volume which helps it fill irregular cavities. Closed-cell foam expands less but packs more insulating value (higher R-value) per inch. We help our clients weigh these traits against climate, building structure, and energy goals.
When Moisture Protection Is a Priority
If moisture is a concern in your space whether it’s a basement, crawlspace, or coastal-facing wall closed-cell spray foam provides the kind of moisture resistance that can prevent long-term structural damage.
We’ve worked with homeowners near the Oregon coast who’ve seen dramatic improvements in indoor air quality and durability after switching to closed-cell foam. It doesn’t just insulate it keeps out water, strengthening walls and reducing humidity inside the home.
Closed-Cell Foam for Crawlspaces, Basements, and Exteriors
Closed-cell insulation is practically impermeable to water. That makes it a smart choice for areas exposed to the elements or prone to dampness. We often recommend it for crawlspaces in Southern Oregon where ground moisture can affect indoor air.
Structural Strength and Long-Term Stability
One of the advantages of closed-cell foam is how it reinforces the surfaces it’s applied to. In attics or roofs, that added strength matters. We’ve had clients notice a quieter, sturdier home simply from this change.
When Breathability and Soundproofing Matter Most
In some parts of a building, moisture resistance isn’t as critical but sound dampening and air movement can be. This is where open-cell foam shines. It allows vapor to pass through, which can be helpful in attics with good ventilation or interior partition walls.
We often install open-cell spray foam for clients who want quieter bedrooms or office spaces. Its sound-absorbing nature makes a real difference in living comfort.
Open-Cell for Attics and Interior Walls
In attics where there’s adequate roof ventilation, open-cell foam provides a cost-effective insulation option. It fills cavities thoroughly and keeps energy bills lower without adding unnecessary weight or rigidity.
Cost Considerations: Open-Cell Is More Budget-Friendly
Open-cell foam typically costs less per square foot installed. When budget is a factor and moisture control isn’t a top priority, this option delivers solid insulation performance and helps you stretch dollars further.
Matching Spray Foam Type to Building Goals
Every property has a unique combination of needs. Some of our clients want the highest R-value possible per inch to meet energy codes in tight spaces. Others prioritize comfort or long-term savings. We help match spray foam type to those specific goals.
Sometimes that even means using both types of foam in the same structure. For instance, closed-cell in crawlspaces and open-cell in attic rafters.
Energy Code Compliance in Oregon
Closed-cell spray foam often allows for thinner insulation layers to meet required R-values, which can be essential in certain builds. We stay up to date on Oregon codes so your insulation doesn’t just work it passes inspection, every time.
Dual Application for Mixed-Use Properties
We’ve insulated properties where different zones need different solutions retail in front, living space in back. In those cases, we might apply open-cell to interior demising walls and closed-cell to perimeter walls. The result is custom-fit insulation that meets every goal.
Your Path to a Protected Home Starts Now with All Foam & Insulation, LLC
Choosing between closed-cell and open-cell spray foam isn’t just a technical decision it’s a choice that affects how your home feels, performs, and stands up over time. At All Foam & Insulation, LLC, we bring the knowledge, tools, and local experience to help you make that choice confidently.
We’re here to answer your questions, walk your site, and recommend the right insulation approach based on your priorities, structure, and budget. Every step is guided by service, transparency, and deep technical skill.
Let’s make your home more comfortable, energy-efficient, and protected.
Call us today at (541) 826-9600 or email [email protected] to schedule a free consultation.
Still Curious? Let’s Dive Deeper with All Foam & Insulation, LLC
1. How do I know which spray foam is best for my home?
Start with how the space is used. Is moisture an issue? Do you need soundproofing? Closed-cell handles moisture; open-cell handles sound. We can walk you through the options on-site.
2. Is closed-cell spray foam always better?
Not always. It’s stronger and more moisture-resistant, but it costs more. For dry, interior areas, open-cell is often the smarter choice.
3. Can I mix both types in one building?
Yes. We do this often. It’s a great way to balance performance and cost.
4. What’s the R-value difference?
Closed-cell foam averages R-6 to R-7 per inch. Open-cell averages R-3.5 to R-4 per inch.
5. Will open-cell foam absorb water?
It can, which is why we don’t use it where moisture is a concern.
6. Does spray foam help with soundproofing?
Open-cell is better for this. Its softer texture absorbs more sound.
7. Can spray foam be used in metal buildings?
Absolutely. Closed-cell works well in metal shops and barns. It adds strength and seals air gaps.
8. What about mold resistance?
Closed-cell foam resists mold because it doesn’t hold moisture. We often recommend it for damp areas.
9. Is spray foam safe for homes with kids and pets?
Once cured, both types are safe. We follow best practices during installation to protect air quality.
10. What’s the installation process like?
We prep, mask, and spray in stages. Most homes are completed in a day or two. We’ll walk you through the plan before we begin.
