Crazy and Complicated Truss Designs – Part 7
Recently I did a job for one of our customers that I got to add yet more insane truss designs to list. By now, I am a regular in this ever-growing column of wacko things people try to make lumber do.
This job came to me and at first glance it wasn’t the nastiest thing I have ever seen, but I knew there would be problems, just not the problems that did arise. The building is your standard apartment complex with the flat roof, negative pitches and even a small hip thrown in.
Overall, judging by the elevation this was a large job in general. The part that made it complicated is the depth of the trusses. In the following pictures you will see exactly what I mean.
Let’s start with this truss. Granted it has middle bearing, the span still doesn’t allow for the 14” depth that runs virtually the entire length. Because of this, the truss was designed as a 2-ply. This truss follows a taller negative pitch on the left and the 14” roof deck on the right.
This profile follows a taller negative pitch on the left and stays down at the 14” roof deck on the right. This truss was run as a 4-ply. While you can’t see the reactions, you can tell by the hanger call outs that there is a massive amount of load hanging into this girder.
This beauty, along with many others that fill in the area, have a 9’ overhang on the left end. That’s right, a 9’ overhang. Ever done one of those? Sometimes the things I see in plans make me laugh.
This truss, based on the span and depth is also a 2-ply. Based on the span of this truss, I was forced to modify the depth of the roof deck just to get it to work as a 2-ply. Any shallower and if was going to be a 3-ply, as it is clear span!
And then there is this inverted pitch gem that spans 48’ and has a 6’ overhang on the right side. This truss is designed as a 2-ply with all 2×6 top and bottom chords. Granted it’s not the most spectacular truss, but I think it represents the crazy things that trusses these days are expected to hold up.
I know these trusses aren’t the coolest looking trusses I have done, but these were some of the most pain in the butt trusses I have dealt with based on the roof deck being so shallow. I hope you all have enjoyed reading these and look forward to learning about any crazy designs anyone else may have.
We welcome guest blogger who wish to share their unique designs, feel free to email one in to continue our series!
View Part 1 in this series here.
View Part 2 in this series here.
View Part 3 in this series here.
View Part 4 in this series here.
View Part 5 in this series here.
View Part 6 in this series here.
Stay tuned for Part 8.
Zach Failing – Design Professional
Gould Design, Inc.