World First 3-Hour Fire Test Means Timber is Safe for High-Rises

Breaking News: Neutral and Arup make all test results publicly available.

Neutral’s fire resistance tests confirm mass timber meets IBC Type I-A standards, with assemblies exceeding the 3-hour threshold under full load conditions.

Developers of North America’s tallest “plyscraper” have achieved a major milestone in the push to build skyscrapers out of timber, after they successfully completed the world’s first three-hour fire-resistance test on a mass timber assembly—a breakthrough that paves the way for adoption of cross-laminated timber (CLT) and glulam in high-rise construction.

The test was conducted at the Southwest Research Institute (SwRI) in San Antonio, Texas, and evaluated the performance of CLT floor decks—supplied by Stora Enso—and glulam beams and columns from WIEHAG. Under fully loaded fire conditions, the assemblies met and, in some cases, exceeded the three-hour threshold required for Type I-A buildings under the International Building Code (IBC)—a classification typically reserved for steel and concrete structures.

“This is the first successful implementation of the three-hour fire test of a mass timber assembly that illustrates the safety and potential of mass timber application in high-rise construction,” Neutral said in a statement, which published the results—report one and report two—for open use by researchers and industry professionals worldwide.

Read the full article, published by Wood Central – Jason Ross –  https://woodcentral.com.au/mass-timber-passes-the-worlds-first-3-hour-fire-test-for-high-rises/?ct=t(EMAIL_CAMPAIGN_20_08_2025)&mc_cid=7281d7cc8a&mc_eid=61dfd8a916