Attic Truss

This week’s truss: Flat Roof Optimization


What would you do to make this truss design more efficient?

Top Chords: 2×4 Southern Pine #2
Bottom Chords: 2×4 Southern Pine #1 or Select Structural (B4, B5)
Webs are 2×4 Southern Pine #3 or #2 (W2, W20)
Building Code: CBC 2022


Loads (psf unless otherwise noted):
TC Live Load 20
TC Dead Load 20
BC Live Load 0
BC Dead Load 10

Wind: 160 mph

Carried trusses with net reactions of 100 lbs downward at 13’10 and 26’ 

The answer will be posted on Thursday!

This is not a production truss! This is simply an example for Truss Tuesday conversation. Join the conversation on LinkedIn.

Updated: Thursday, March 14th, 2024


Here are the first things we would change:

  1. Offset the splices. Lining them up like this creates weak points in the chords
  2. Position a vertical underneath each point load


The results:

  • No more Select Structural in the bottom chords
  • Total plate area reduced by 25%