ladder truss cantilever length 1

[cfarmer]

Is there a code specified maximum cantilever length for a ladder truss (2x4) fastened directly to the face of a truss such as on a gable end of a roof?
That is, with the ladder fastened directly to the first truss and not over top of the gable end wall and then fastened to the first truss inside the gable end as is the norm.
I was thinking between 6" and 8".

 

[ERV]

cfarmer,

In this case the roof sheathing is actually acting as the cantilever, the type of roof sheathing would determine the maximum overhang. Fascia would be attached directly to the roof sheathing and "ladder framing" is not needed. Check local building codes to see if this allowed in your area.

 

[AlohaBob]

I questioned this once. I was concerned that at some time, someone would stand out at the edge and the sheathing split and break. What if the sheathing is rotted? The framing below seemed unstable.

I looked carefully how the framing works. The nailing at the rail and face of the gable wall provides the shear transfer. The rung top surface provides the tension component of the truss. If you wish, you can provide a strap across this block back into the roof framing across blocking between the trusses to develop the tension. Or for a very narrow ladder, the sheathing may provide the tension component. The bottom surface of the ladder provides the compression force for stability. It needs a reaction too.

Without attention to detail, it's likely the ladder framing is unstable and the only support is the cantilever plywood decking. With the attention to detail, the ladder framing can provide stability for vertical load.

And the greater the projecting length, the more rigorous the detailing. The carpenters are fond of this framing, so fortunately it lends itself to analysis.