LP FlameBlock

For Code Officials

Engineered For Code Compliance

LP® FlameBlock® Fire-Rated OSB Sheathing is a component of code-compliant fire-rated wall assemblies and roof deck applications. It installs easily like regular OSB, without extra components.

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Code Approved

  • ICC-certified (ESR-1365)
  • Class A and 30-Minute Flame Spread Rating (ASTM E84, UL723)
  • Combines flame-spread resistance and burn-through resistance
  • 15-Minute Thermal Barrier Protection (UBC 26-2)
  • Component of fire-rated interior and exterior wall assemblies and roof decks

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Exposure 1 Weather Resistance

LP® FlameBlock® carries the Exposure 1 classification which certifies that it's able to withstand normal exposure to moisture during construction. Interior-grade FRT plywood must be protected from precipitation during construction.

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Technical Support And Education

LP provides easy access to any code approval reports and technical documents you need, including installation detail drawings and ESR reports.

CODE COMPLIANCE AND FIRE PERFORMANCE

Certification and Testing

  • Certification ICC-certified (ESR-1365) as a code-compliant component of fire-rated wall assemblies and roof deck applications
  • Class A and 30-Minute Flame Spread Rating (ASTM E84, UL723)
  • Meets 15-Minute Thermal Barrier requirements (UBC 26-2)
  • CALFIRE/OSFM code-approved (CBC Chapter 7A) for use in exterior walls, eaves and soffits in California WUI Zones

Relevant Listings/Assemblies

  • 2-hour Load-Bearing Fire-Rated Exterior Walls:
    • UL Listing BXUV.U349
    • UL Listing BXUV.W408
    • UL Listing BXUV.W408 Extended
  • 1-hour Load-Bearing Fire-Rated Exterior Walls:
    • Intertek Listing LPB/WPPS-60-01
    • UL Listing BXUV.U348
    • UL Listing BXUV.V311 
  • 2-hour Load-Bearing Fire-Rated Interior Walls:
    • UL Listing BXUV.U350
  • Roof Decking Application to satisfy vertical continuity requirements for fire walls

Weather Resistance

  • Exposure 1 Classification – Certified to withstand normal exposure to moisture during construction delays

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