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
MSRLPC Streamlines Design Values Comparison with New Online Tool MSR Lumber Producers Council The MSR Lumber Producer Council’s new Design Values Comparison Tool makes it possible for component manufacturers and other lumber buyers to easily build a comparison table based on species, size, and grade that includes design values for both visually graded and machine-graded dimensional... Read More June 2023 Issue #15287 Page 68
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
The Development of the Truss Plate, Part X: Split Decision on Truss Plates Joe Kannapell Four distinctly different types of truss plates came onto the market in the 1950s, but only two made it into the 1960s: the short toothed and the long toothed, neither requiring nails. These two types continued to evolve over the next decade, although along distinctly different paths, and under... Read More May 2023 Issue #15286 Page 10
Should We Seal All Engineered Drawings? Glenn Traylor Recently, while conducting an ANSI/TPI audit, a splice caught my eye. When I investigated further, I realized that the bottom chord of the truss I was investigating had a very short, 2” chord segment. I immediately assumed the truss builders had cut a short block to make up for a miss-cut... Read More May 2023 Issue #15286 Page 37
Design Connections: Training New Designers Geordie Secord Last month’s article, “The Designer Shortage—Where Can We Find Them?”, offered some suggestions for finding new component designers. This month, I have some suggestions for training those new hires effectively. And bear in mind, as I mentioned last month, I think it is... Read More May 2023 Issue #15286 Page 80
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
The Last Word: Truss Machinery Follows the Plates Joe Kannapell Throughout the 1950s, plate manufacturers kept busy improving their plate designs, while they paid scant attention to the machinery that CMs needed to embed them. But, in the 1960s, they began focusing heavily on machinery and laid the foundation for developments that would shape truss... Read More May 2023 Issue #15286 Page 124
The Development of the Truss Plate, Part IX: The Case of the Century Joe Kannapell Among our industry’s unsung heroes, Walter Moehlenpah takes a close second place behind Cal Jureit. Both built pivotal, pioneering businesses, Jureit through his truss plate and Moehlenpah through his truss machine. Yet Jureit was bound to have the upper hand, as he was the truss... Read More April 2023 Issue #15285 Page 10