LP FlameBlock

Proven To Slow Down The Spread of Flames

  • OSB panels are available in 4 foot nominal widths and 8, 9, or 10 foot lengths
  • Available performance categories: 7/16˝, 15/32˝, and 19/32˝
  • Available on APA Exposure 1 rated OSB


Features and Benefits

Resisting Flame Spread
Evaluated by ICC-ES, LP® FlameBlock® Fire-Rated Sheathing combines flame-spread and burn-through resistance in applications that meet fire code requirements.
Do More with Less
A building solution that provides strength, savings and easy installation – at an affordable price.
Exceed Expectations
Combined flame-spread and burn-through resistance bolster a home’s fire resistance capabilities, improving the homeowner’s peace of mind.
Design Freedom
Structural design values are not limited, providing more flexibility in designing wall openings, frames and bracing.
Multifamily building with FlameBlock installed
Sales Tools
Find out how LP® FlameBlock® Fire-Rated Sheathing can benefit your build.

Product Catalog

Architectural Specifications

Assembly Reference Guide

Portfolio Product Guide

FlameBlock panels stacked
Technical Documents
Get the details on LP® FlameBlock® Fire-Rated Sheathing installation.

Installation Instructions


Safety Data Sheet

Warranty Information

Building with FlameBlock panels installed
Building for Resiliency
LP® FlameBlock® Fire-Rated Sheathing helps meet fire code requirements.

Guide to Fire Resistance

UL Fire Ratings to Know

Factoring Resiliency into Code Requirements

Helping Prevent Row Home Fires

Putting Our Fire-Rated Panels to the Test

See how LP® FlameBlock® Fire-Rated Sheathing performs in a controlled product demonstration compared to untreated OSB.

How It’s Made

To create a standard OSB panel, LP’s innovative manufacturing process combines wood strands oriented in cross-directional layers with waxes and resins. Then, to create LP® FlameBlock® panels, LP’s proprietary non-combustible, fiberglass-reinforced Pyrotite® treatment is added, which combines flame-spread and burn-through resistance. This creates a product that not only resists fire damage but meets code, provides design flexibility, and also offers the strength and structural integrity of traditional OSB panels.

Infographic of FlameBlock board

Fire Resistive Technology

Go to work with a building solution that meets building code requirements for fire-resistant construction while increasing structural ratings. Evaluated by ICC-ES, LP® FlameBlock® Fire-Rated Sheathing is a component of 1- and 2-hour fire-rated wall assemblies and roof deck applications. It combines flame-spread and burn-through resistance to give your customers peace of mind.

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