Designers of mass-timber structures in the U.S. have made inroads recently. Still, the building material has struggled to gain popularity there due to perceptions of mass-timber being flammable — and dangerous — among other things. Supply-side challenges, for one, have made it more difficult for the mass-timber products to gain popularity in the U.S. Mill owners have expressed little interest in producing the product until there is a steady demand, but demand is unlikely to grow until material prices drop and local codes recognize the new material. Mass-timber advocates argue that the material is resistant to fire because it chars rather than burns, protecting and preserving the strength of the underlying layers.