Not only is CLT safe, it is the only renewable structural building material.
A recent letter, “Do more testing,” from the Carolina Ready Mixed Concrete Association calls for fire tests of mass-timber construction panels, which have already been completed. In addition to years of testing that have taken place in Canada and overseas, five additional fire tests were completed on cross-laminated timber (CLT). Interestingly, representatives from the National Ready Mixed Concrete Association were present and witnessed the promising results.
In conjunction with the International Code Council, American Wood Council and U.S. Forest Service Forest Products Laboratory, the five tests were completed on a full-scale, multi-story mass timber apartment building in May and June of this year. The tests ranged from unsprinklered to sprinklered, exposed CLT and CLT covered with gypsum wallboard. The results of each test showed CLT, even when exposed, maintained fire resistance.