Floor Truss Technology, Part I: Parallel Chord Trusses Joe Kannapell Floor trusses have been golden for the component industry for over half a century, and their origin is worth recounting and celebrating. Because of their flexibility and utility, wood trusses dominate apartment construction and have taken it up to 5 stories. Getting there, however, has required... Read More June 2023 Issue #15287 Page 10
Are You Providing Enough Information to Avert Failures? Glenn Traylor Recently, when a building owner started getting leaks in the roof and noticed unusual variations in the ceiling, I was asked to do an inspection to determine the best way to correct a deflection problem. Upon inspection, it was very evident that the roof trusses had not been installed correctly... Read More June 2023 Issue #15287 Page 37
Load Duration Factor MiTek Staff Lumber has ability to handle higher stresses under shorter periods of time. This characteristic is known as Load Duration Factor. Load Duration Factor typically ranges from 0.9 to 1.6 and is based on the amount of cumulative time the load is applied to the structure. Per the National Design... Read More June 2023 Issue #15287 Page 92
Contributing to a New Youth Scout Den in New Zealand Simpson Strong-Tie Staff Our Simpson Strong-Tie New Zealand branch was established in 2010 and helps provide Simpson Strong-Tie products to our friends in New Zealand. Recently, the branch had the opportunity to help a local scouts club build a new den to accommodate their growing club. [For all photos, See PDF or... Read More June 2023 Issue #15287 Page 102
Correctly Defining Truss Members MiTek Staff When designing trusses for special loads or special conditions, it is important to define the individual truss members correctly. Without proper member definitions, trusses could be inadvertently under-designed and/or have incorrect analog. The most common member types are webs and chords. Top... Read More May 2023 Issue #15286 Page 92
Mass Timber Diaphragm Options with Four Different Connection Types — How Our LDSS48 Light Diaphragm Spline Strap Evolved Paul McEntee Floors and roofs on mass timber buildings are constructed from large panels of engineered wood, such as cross-laminated timber (CLT) or mass plywood. Designers join these prefabricated panels together on site to create a structural horizontal diaphragm to transfer wind and seismic loads to the... Read More May 2023 Issue #15286 Page 96
Should We Consider “Delivery” Load Cases? Glenn Traylor Years ago, truss design was focused on a simple calculation that determined the final forces that would be considered to be imparted on a truss component. These simple forces were used to determine the design. Things like snow, wind, and building materials weights were generally the only... Read More April 2023 Issue #15285 Page 35
Bracing on Truss Design Drawings MiTek Staff Trusses are designed as individual components to resist the in-plane stresses resulting from the loads applied in the same in-plane direction. To resist out of plane forces, adequate bracing/restraint is required. In absence of designed temporary and permanent bracing plans, BCSI (Building... Read More April 2023 Issue #15285 Page 104
How to Accommodate Misplaced Shearwall Anchorage Simpson Strong-Tie Staff For several years, the Simpson Strong-Tie Strong-Wall® research and development team has kicked around the idea of developing an “adapter” that would allow for field substitutions or accommodate misplaced Strong-Wall anchorage. The Strong-Wall WSWH high-strength wood shearwall... Read More April 2023 Issue #15285 Page 108
Design Connections: Is There Ever Just One Right Way? Geordie Secord If you have spent your truss career in one region, and even more so with just one company, you will have seen that, generally speaking, your competitors and co-workers tend to frame houses essentially the same way. Only when you are exposed to a different company or region do you start to see... Read More March 2023 Issue #15284 Page 80