FMI-EPS R+ Fanfold Insulation provides a durable, easy-to-install underlayment for siding, roofing, and re-cover projects. Manufactured from high-performance Expanded Polystyrene (EPS) with multi-ply polymer facers, R+ Fanfold combines thermal efficiency, moisture resistance, and dimensional stability in one economical product.

Available in convenient 2’ x 4’ panels or 4’ x 50’ fanfold bundles, this insulation is designed for fast installation and long-term protection. The laminated facers resist tearing, warping, and plasticizer migration, ensuring reliable performance for the life of the building.

• Lightweight & Easy to Handle – Cuts quickly with standard tools and lays flat on the jobsite.
   
• Moisture Resistant – Facers protect the EPS core and provide added resistance to water absorption.
   
• Thermal Performance – Provides an R-value of 3.85–4.76 per inch for energy savings.
   
• Cost-Effective – More insulation performance per dollar compared to other underlayments.
   
• Durable – Withstands jobsite handling, impact, and long-term service temperatures from -65°F to +165°F.
   
• Environmentally Safe – 100% recyclable, with no CFCs, HCFCs, HFCs, dyes, or formaldehyde.
   
• Warranty Protected – Backed by a 20-year R-Value warranty.
   

• Fan-Fold Bundles: ¼” to 1” thick, 4’ x 50’.
   
• Sheets: 3/8” to 5-3/8” thick, 4’ x 8’.
   
• Available in a range of compressive strengths to meet project requirements.
   

• Residential & Commercial Siding – Smooth backing surface for vinyl, aluminum, and other sidings.
   
• Roofing Recovery Board – Protects membranes in single-ply systems.
   
• Sheathing Insulation – Adds thermal performance and moisture protection to walls.
   
• General Construction – Void fill, protective packaging, and other utility uses.
   

With its combination of strength, thermal performance, and affordability, R+ EPS Fanfold Insulation is the ideal choice for siding, roofing, and wall applications.

📞 Contact us today at (208) 777-8485 to request a quote or learn more about our EPS fanfold insulation solutions.