Crazy and Complicated Floor Truss Designs

Crazy and Complicated Floor Truss Designs

A while back I did a piece on crazy roof truss designs. You can view that article here. Things being done in roof trusses I had never seen before let alone designed by myself. Well I am here to tell you, that just about anything that can be done in a roof can also be done in a floor. Well maybe not anything, but you get my point!

Recently I was given a plan to design a floor system for. At first glance it looked like a box, so I said to myself: “This won’t be so bad, it’s just a box. Add ad LVL beam here, girder there, and viola!” Then I started to dig into the architectural plan… To my surprise, the plan showed the kitchen being stepped up 3’ higher than the main part of the house. The second floor sits right on top of it. Hmmmmmmmmm. Now there are also steps in the second floor but not where the kitchen ceiling transition happens. This floor that originally looked to be pretty simple was appearing that it was going to take all my remaining brain cells to figure out.


As you can see from the layout, the section that I referred to have a 3’ raised ceiling! When I was first looking at it, trying to decide which route to take, I was left scratching my head. I could have made all those back trusses the same thickness and let the building underframe or I could make the trusses 5’ deep on the left to make up for the 3’ difference. I went with the 5’ option after discussing it with a colleague.


Going with the 5’ deep floor truss wasn’t really the issue, it was trying to figure out how to carry the trusses that were higher up at the kitchen level and the ones that were down low of the based ceiling height. The girder truss that I came up with is what encouraged me to write this article. It was something I had never done before or had seen.


As you can see below, this truss took a lot of Versa Truss to get it to work.

  • The bottom chord carries all the trusses that sit at the standard ceiling height
  • The middle chord carries all the kitchen trusses which are at the 3’ taller ceiling height
  • The top chord on the right is dropped. This was necessary to carry a cantilevered 2×6 that extends out. That extension carries the taller floor which runs over the top of the lower floor system and the stairs at the lower right of the layout. Since the bearing location was fixed, I had no choice in the matter!


Unlike my crazy roof truss collection, these floors may not surprise anyone, they sure surprised me….especially the girder. I had a good dose of the Florida design market on this one! I think this industry is pretty special for the simple fact that I have been designing for 8 years and just about every day I am amazed at what we can accomplish with wood trusses. It allows my creative instinct to come out each and every day.

What types of unique floor designs have you seen? Were they crazier than this?

Zach Failing

Design Professional

Gould Design Inc.

2 thoughts on “Crazy and Complicated Floor Truss Designs