The National Design Standard for Metal Plate Connected Wood Truss Construction, ANSI/TPI 1-2022 has been updated to require a design load check that accounts for a Person Loading of a roof truss chord without structural wood sheathing. As discussed in the ANSI/TPI 1 Commentary, this loading...

The advent of floor trusses gave us new insights that continue to be refined today. They also gave us a peek into whole house design with the promise of a fully componentized house. For the first time, they challenged us to build something that people could live on top of, rather than just...

ANSI/TPI 1 is a practical guide to manufacturing metal plate connected wood truss. It considers rational expectations and reasonable manufacturing capabilities that help ensure a sound product. Due to the nature of wood, cutting equipment and processes gaps do occur. These gaps can cause...

As I approach four decades in this industry (!), the list of building code and design requirements that seem odd to me continues to grow. I am the first to acknowledge that the primary goal in designing a home is, and should be, occupant safety. But there are some requirements and...

Top chords are usually braced by roof sheathing. Roof sheathing provides effective lateral bracing when nailed directly to the top chord. In cases where roof sheathing cannot be directly applied to the top chord, purlins are used to prevent lateral buckling of truss top chords. The Truss...

One of the first mixed-use designs I worked on as a consulting structural engineer was a four-story wood-frame building over two levels of parking. Designing the main lateral-force-resisting system with plywood shearwalls was a challenge for this project that required new details to meet the...

With the recent passing of Tom Denig, which was not long after Gene Toombs’, we should take a moment to reflect on their stunning success, gained while working separately and together. They both took over highly technical companies in the early 1990s, Denig at Trus Joist and Toombs at...

It wasn’t enough for Jack Schmitt, President of Truswal, to introduce wood-web floor trusses. He also had to demonstrate how to build them, and that required a special machine. Schmitt turned to his trusted associate, Carl Virta, to come up with a process, and Carl knew who could help him....

MiTek Engineering software gives you two options to input snow load – Ground Snow and Roof Snow (flat roof snow). What is the difference between ground snow and flat roof snow? Ground snow load, pg, is obtained directly from the American Society of Civil Engineers Standard (ASCE 7)...

Simpson Strong-Tie recently released an updated model of our H1 – now the H1A. As a consulting engineer, I remember how much I disliked updating my standard details when products were discontinued. I thought it would be informative to explain the modifications and some of the reasons for...