The Foam Sheathing Committee (FSC) serves as a manufacturing-driven organization focused on developing solutions to building code issues and promoting the proper technical use of foam sheathing to the construction industry.

Foam Sheathing Committee Compendium

A growing collection of technical, educational and training documents for Foam Sheathing Committee members from the Applied Building Technology Group.

Foam Sheathing Committee (FSC) Members:

Atlas RoofingDowGAFHunter PanelsJohns ManvilleKingspan Insulation LLCOwens CorningRMAX



Foam Plastic Insulating Sheathing (FPIS) Products are offered in three types:

  • Expanded Polystyrene (EPS) - ASTM C578
  • Extruded Polystyrene (XPS) - ASTM C578
  • Polyisocyanurate (Polyiso) - ASTM C1289

FPIS products also come in many thicknesses to accommodate almost any end use.

FPIS Products shall be installed in accordance with:

Step 1

Place Insulation Boards

  • Ensure wall is square and true
  • Align boards with bottom edge of wall

  • Verify stud spacing, blocking, and bracing requirements with manufacturer
  • Provide framing or blocking for attachment of siding and trim at transitions
  • Seams should not be visible from interior unless allowed by manufacturer

Step 2

  • Typical detail for FPIS wall assembly attachment
  • Fasteners shall meet penetration requirements per manufacturer’s instructions and code requirements

(a) FPIS
(b) Fasteners
(c) Structural Sheathing (as required)
(d) Framing
(e) Cavity Insulation
(f) Interior wall finish

Step 3

Attach Insulation Boards

Space fasteners per manufacturer’s instructions

  • Around edges of panel
  • Through panels and into interior members

  • Drive nails flush and snug
  • Do not overdrive nails
  • Do not underdrive nails

Step 4

Trim Boards at Openings

  • Trim boards at all window and door openings
  • Cover all framing with FPIS
  • Fit joints tightly

Step 5

WRB and Flashing

  • Ensure that a code compliant water-resistive barrier (WRB) and required flashing is provided
  • If using FPIS as a WRB: 
    • Seal all joints and openings and penetrations per manufacturer’s installation instructions

  • At pipe and other small penetrations, seal gaps with silicone or expanding spray foam sealant
  • Seal joints and openings with joint tape per manufacturer’s instructions

  • Repair damaged areas per manufacturer’s instructions.