On Monday October 17 the Reliable's held an open practice to demonstrate the difference in burn rate between conventional timber construction and engineered I-joist construction. A side by side demonstration was set up to show a direct comparison. The joists were loaded and a fire was ignited below simultaneously. As the fire load began to grow it quickly became evident that the I-joists were burning at a hotter, higher rate. As expected the I-joists failed first, at around 24 minutes. The bottom chord of the joist burned out and at that point failed. The time was skewed because it was loaded as a static, dead load. In a working structure fire where firefighters will be present the joists will fail much quicker because of the oscillation caused by movement above. More and more homes are being constructed using wood I-joists and need to be evaluated differently than a conventional stick frame home.
