Although not defined in the 2015/2018 IBC, this presentation includes an overview of “mass timber” which is any product currently permitted for use in Type IV construction such as cross-laminated timber (CLT), structural composite lumber (SCL), glued laminated timber (glulam), mechanically laminated decking (aka nail-laminated timber, NLT), and large section sawn timbers. This presentation will provide an overview of changes to the 2015 and 2018 International Building Code (IBC) related to mass timber construction. CLT was first incorporated in the 2015 IBC and additional types of SCL were added to Type IV (heavy timber, HT) construction. The 2018 IBC reorganized heavy timber provisions aiding clear application of heavy timber construction requirements while also providing for separate application of code provisions that allow or specify the use of “mass timber” elements outside of Type IV construction.

Learning Objectives:

1. Identify Type IV construction including height and area allowances
2. Recognize new mass timber products such as CLT
3. Describe new provisions in the 2015 IBC related to CLT and SCL
4. Summarize new provisions in the 2018 IBC related to mass timber products and Type IV construction

Funding provided in part by the Softwood Lumber Board.