Tall mass timber is an industry term to identify mass timber buildings, constructed of mass timber elements, that exceed current height limits for wood buildings set by the International Building Code (IBC). Mass timber includes any product currently permitted for use in Type IV construction, such as Cross Laminated Timber (CLT), Structural Composite Lumber, glued-laminated timber, and large section sawn lumber. Because of the unique structural and fire resistance characteristics of solid timber walls and floors (CLT) and mass timber structures, new provisions have been approved for the 2021 Edition of the IBC for tall mass timber buildings up to 18 stories.