March 2019 APA Update

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Wind-Resistant Building

Tornado season is back. Although monster storms get a lot of attention, 95 percent of tornadoes are weaker (EF0–EF2), and homes that are built with wind-resistant construction details can withstand them. Building a more wind-resistant structure does not require a lot of expense, but it does require attention to detail. Check out APA’s resources on wind-resistant construction to learn more.

Increase the wind resistance of sheathing panels with 4-inch oc nailing on boundary and 6-inch oc nailing at intermediate supports Design Guide: Building for High Wind Resistance in Light-Frame Wood Construction outlines nine easy construction techniques that are recommended to improve a house’s structural performance in high wind. The techniques focus on the structural shell and connection details and are simple, straightforward and cost-effective.




Failure of wall constructed with flexible structural sheathingOn-Demand Webinar: After the Storm—Building for High Wind Resistance includes an overview of high wind forces, the importance of a continuous load path and how good design and construction practices can improve the storm resistance of buildings. Learn more about APA’s above-code recommendations for wind-resistant building, as well as how attention to connection details, understanding lateral load concepts and recognizing common failure modes seen in storm damage assessments can help builders cost effectively build a safer home.





Product Advisory: Performance of Flexible Structural Sheathing

Shear wall performance tests by Clemson University, the University of Oklahoma and APA's research center evaluated the performance of walls constructed with five flexible (laminated fiber) sheathing products, some of which are as thin as 0.078 inch. Test results from all labs showed that manufacturers' product evaluation reports overstate their lateral load resistances by as much as 42 percent. This raises questions related to the safety and reliability of a structure designed with these products. See all test results, including photos, in the Product Advisory.


PRR-401 Performance Standard for APA Rim Boards

This standard provides the performance requirements, including dimensions and tolerances, test methods and quality assurance for APA-trademarked Rim Boards. Includes mandatory design properties and nonmandatory adjustment factors and ASD-to-LSD conversion factors.