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Meet the Fire Code—and Your Design Goals

Posted in Industry News

Meet the Fire Code—and Your Design Goals

Do you think meeting code requirements means sacrificing major elements of your design? Think again. Thanks to advancing technology, multifamily projects can maintain large window openings and full interior spaces, while meeting fire protection elements within the International Building Code.

One such innovation is LP® FlameBlock® Fire-Rated OSB Sheathing. Featuring an ignition-resistant Pyrotite® coating that slows the effects of heat and flames, FlameBlock OSB Sheathing is a listed component in fire-rated interior wall assemblies, exterior wall assemblies, and roof deck applications. It carries a Class A and 30-minute flame spread rating.

At the same time, the sheathing offers the same load/span and shear-strength design values as untreated wood structural panels of the same thickness. This provides for more flexibility in design of wall openings as well as more options in framing and bracing to meet structural requirements. It also reduces dead load and wall thickness versus common alternative assemblies.

FlameBlock Fire-Rated OSB Sheathing delivers higher design values than FRT plywood at the same thickness and has the versatility to be used in Type II, III, and V construction.

The project team for the AVA apartment building in Washington, D.C.,- turned to LP FlameBlock as a key component to achieving a modern, hip design that would attract younger renters while keeping rental costs reasonable.

“In Type III construction, you need to meet fire ratings and lateral bracing requirements,” says Rohit Anand, principal architect for KTGY. “FlameBlock is a composite product that really takes care of both needs in one application step.”

“We have one of the largest development platforms and continue to do more high-density wood construction at infill locations,” adds Rick Morris, senior vice president for Avalon Bay. “We’re building five-story to six-story buildings. FlameBlock helps us go high and provide more density. We don’t have to go to concrete or some of the other materials that are more costly and challenging to work with. FlameBlock is a product that really fills a need that was present in the marketplace.”

Because LP FlameBlock panels are installed with the same tools and fasteners used for installation of other structural sheathing panels, Morris says his carpenters who are familiar with wood construction have not experienced any issues when installing the product.

Morris also explained that in certain siding applications, LP FlameBlock Sheathing seems to provide better attachment detail. This is because the proven fastener-holding ability of LP FlameBlock Sheathing can simplify installation of exterior facing materials, potentially saving additional labor and time.

David Kelley, project manager for architecture firm 2PA, also experienced these advantages with the design of The Gibson, a 250-unit Type III-A multifamily project in Charlotte, N.C. Kelley wanted to utilize an exterior wall assembly that did not require one or more layers of gypsum sheathing on the outside, an objective he achieved through the use of LP FlameBlock OSB. A total of 6,500 square feet of LP FlameBlock sheathing was used on the exterior wall of the UL349 assemblies.

Without the additional layers or obscure installation requirements, the project saw labor savings, as well. In addition, “The biggest advantage of FlameBlock was that it was easily accepted by AHJA (Authority Housing Jurisdiction) and was listed in the UL,” says Brandon Pitts, project manager on the Gibson build site.

To see more examples like AVA and The Gibson, visit

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