scope:

Purpose

This Design Guide is written for structural engineers who are designing hybrid steel-framed structures with mass-timber floors. It is intended for engineers who are experienced in structural steel design but not necessarily experienced in the design of mass timber or mass-timber hybrid structures. While this Design Guide is intended primarily for structural engineers, the design of hybrid steel-framed structures with mass-timber floors requires a holistic approach that considers fire performance, acoustic considerations, and an understanding of sustainability principles. Background information and high-level advice for these topics are covered in the Design Guide to provide the structural engineer with resources during early design stages to make informed design decisions.

This intent of this Design Guide is to provide a comprehensive view of the design issues associated with hybrid steel-frame structures with mass-timber floors in the United States. The intent is not to replicate detailed information that has been published in other code and industry documents. Detailed information regarding mass-timber design can be found in the following suggested resources:

• National Design Specification (NDS) for Wood Construction (AWC, 2018)

• Calculating the Fire Resistance of Wood Members and Assemblies (AWC, 2021a)

• Mass Timber Design Manual (Think Wood, 2021)

• U.S. Mass Timber Floor Vibration Design Guide (WoodWorks, 2021b)

• Mass Timber Buildings and the IBC (AWC/ICC, 2020)

• CLT Handbook (FPInnovations, 2013)

• Standard for Performance-Rated Cross-Laminated Timber (APA, 2019)

• Nail Laminated Timber U.S. Design & Construction Guide (BSLC, 2017)