What Is Structural I Rated Sheathing?

Structural I Rated Sheathing provides greater cross-panel strength and stiffness for use in particularly demanding portions of a build such as shear walls, and floor and roof diaphragms. When using Structural I Rated Sheathing, your build can stand up to whatever comes its way with increased structural reliability.

Materials and Fabrication of Structural I OSB

Typically manufactured in 4-foot by 8-foot or similar panels, Structural I OSB is made to be consistent and strong: free of knots, grain defects, core voids, splits and other irregularities. Structural I OSB panels are created with wood strands mixed with resins. These strands are arranged in layers for dimensional stability and bonded under heat and pressure. For additional moisture resistance, the panels are sealed on all four edges.

Advantages of Structural I OSB

Structural I OSB sheathing offers many benefits and helps you build with confidence knowing that your structure will stand tall for years to come. Here’s why:

Strength & Stiffness
Struc I OSB engineered wood panels provide higher cross-panel strength and stiffness, and higher racking strength than standard sheathing. For the toughest portions of your build, it offers the strength you need for demanding applications.
A Variety of Applications
Structural I OSB panels are suited for use as floor and roof diaphragms and shear wall sheathing when extra capacity is needed. With OSB rated Structural I, you can bring added strength to your build.
LP WeatherLogic Structural I Rated Sheathing
LP WeatherLogic® Air & Water Barrier
Now available with LP OSB that is APA Structural I Rated Sheathing, LP WeatherLogic panels not only seal out moisture and air—they bring increased stability to your build for increased energy and installation efficiency.

Limitations of Structural I Rated Sheathing

While ideal for many applications, as with any untreated sheathing, there are some limitations to Structural I Rated Sheathing. Here are a few ways this material should not be used, as well as preventative measures that should be taken to preserve the panels’ quality.

  • Structural I sheathing panels are not for unprotected exterior use; they must be covered with siding panels or other exterior cladding or roofing.
  • Additional protective measures are recommended for extended adverse weather conditions (however, thickness swell caused by temporary moisture exposure during active construction will not affect performance).
LP WeatherLogic Combo Panel

Structural I Technical Specifications

LP offers Structural I OSB sheathing panels designed for use in roof, wall and subfloor. Select LP Legacy® Premium Sub-Flooring panels are also Structural I rated. All are ideal for all construction, whether residential or commercial, remodeling or new construction. Structural I OSB panels comply with the following:

  • Quality verified by APA
  • Manufactured in conformance with U.S. Voluntary Product Standard PS2, which is recognized in the IBC, IRC and ICC-ES Evaluation Report ESR-2586

Looking for More Information?

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LP WeatherLogic® Air & Water Barrier

Check out the LP WeatherLogic page to learn more about OSB that stands up to tough conditions.

LP Structural I Rated Sheathing

Discover more details about APA rated sheathing and Structural I Rated Sheathing.

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