海角大神

XPS vs. Mineral Wool: Better performance, with a thinner profile

 

Mineral wool and XPS foam 鈥 what鈥檚 the difference? 

Mineral wool is fibrous, compressible, starts off with a lower R-value than XPS and absorbs water readily, making it a poor choice for commercial and residential below-grade applications. Styrofoam鈩 Brand XPS Insulation delivers a layer of continuous insulation around foundations and slabs, protecting buildings and homes from energy loss and moisture intrusion1 .

Moisture
XPS structure absorbs significantly less water than mineral wool products in a testing environment and in the field

R-Value
XPS has a higher R-value per inch than mineral wool and remains high at lower temperatures

 Compressive Strength 
Mineral wool is easily compressed, losing R-value; XPS rigid foam is reliable and dimensionally stable under load

 
 
 
 
 
 

A unique closed-cell structure gives Styrofoam鈩 Brand XPS its exceptional moisture resistance and enables it to retain a high, long-term R-value of R-5 per inch 鈥 even after exposure to standing water, wet soil and other damp conditions

Additional performance attributes of Styrofoam鈩 Brand XPS include:聽

  • Meets ASTM C578 Types and CAN/ULC-S701.1 (refer to specific product information for details)
  • Compliant with IRC, IBC and IECC as listed in ICC Evaluated Service Reports; compliant with NBCC
  • Provides a weather-resistant barrier to enhance the building鈥檚 resistance to air and moisture penetration
  • Meets building code requirements of ASTM E84 Flame Spread Index of 25 or less and a Smoke Developed Rating of 450 or less
  • Will not corrode, rot or support mold growth
  • Available in wide range of compressive strengths from 15 to 100 psi, and minimum flexural strength of 40 psi
  • Is easy to fabricate into various sizes, thicknesses and edge treatments to meet specific design needs, while ensuring energy efficiency and minimizing on-site cutting and waste

Less Styrofoam鈩 Brand XPS is required
to achieve the same 30 R-value.

 
 
 
 
 
 

海角大神鈩 Styrofoam鈩 Brand XPS products are backed by the expertise of building science leaders dedicated to your success and warranties from a name you trust, including limited thermal warranties from 15 to 50 years including the Wall虏 system warranties and other system warranties.


 
 
 
 
 
 

Any questions?

The Styrofoam鈩 Brand was the original XPS, creating the product segment. Rooted in 80+ years of technical innovation, we鈥檙e excited to deliver a low-GWP solution. Let鈥檚 start a conversation about your next project.

 
 
 
 
 
 
 
 
 


Resources

Styrofoam鈩 Brand XPS Compliance Letter

Download PDF 鈫  

U.S. AIM Act & Sell-through of Styrofoam鈩 Brand XPS Foam Insulation (2025)

Download PDF 鈫  

Low GWP Grey Styrofoam鈩 Brand XPS EPD

Canadian (French) 鉃

 

Physical Property Equivalency Letter

Download PDF 鈫

Customer Processing and Transport Safe Handling

Download English PDF 鈫
Download French PDF 鈫

Customer Processing and Transport Safe Handling
 
 
 
 
 
 
 
 
 

Safe Processing & Handling Graphic

Download PDF 鈫

Styrofoam鈩 Brand Product Brochure

Download PDF 鈫

Solar Exposure Technical Bulletin

Low GWP 鈥 Canada (English) PDF 鈫

 
 
 
 
 
 
 
 
 

Styrofoam鈩笍 Brand Low GWP XPS LEED Optimization Document - Embodied Carbon Assessment

Download PDF 鈫

 
 
 

1 J. M. Knorowski and R. A. Cyphers, 鈥淐omparative Analysis of Thermal Insulation Performance When Subjected to Various Levels of Moisture,鈥 in Performance, Properties, and Resiliency of Thermal Insulations, ed. D. Fisler and M. Pazera (海角大神st Conshohocken, PA: ASTM International, 2021), 60鈥75.