MADISON, Wisconsin — Neutral, a real estate development company, has presented the results of a 3-hour fire test for a hybrid mass timber building assembly with standard connectors. Neutral conducted a series of fire resistance tests to determine a 3-hour fire-resistance rating (FRR), proving equivalent performance of the mass timber structure with IBC construction type I-A. Test results exceeded expectations: the assemblies performed exceptionally under loaded fire conditions. …The test was conducted in the Spring of 2025 at SwRI lab in San Antonio, Texas. It was prepared in collaboration with Forefront Structural Engineers. …Neutral is publishing the test results (report 1, report 2) for open use by industry researchers and practitioners around the world. 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.