Unusual Alteration to Trusses

Hi guys! Encountered an unusual alteration in some trusses today and wanted to get some input as to weather or not they should be called out and to what extent. The attic had some other moisture related issues and some evidence of pest infestation but these trusses being altered with these stringers running along the underside of the sheathing were something I hadn’t seen before. Any thoughts?

Thanks everyone!
Ray Pollard
47º North Home Inspections

Never seen it before, but may be a plus for snow load. How far north are you?

In all my building career I have never come across that either.
The fact that the top chord of the truss is a 2x6 in lieu of the common 2x4 tells me that it might have been designed that way for a purpose.
I would try to get documents or drawings from the owner if he is the original owner of the dwelling.
If not document what you see.

Never mind I looked it up, you get quite a bit more snow than me!

As Marcel said it was probably designed that way, doesn’t look like something done on site.

Awesome. Thanks for the input guys!

Thanks so much Marcel!

That alteration is not allowed.

Do we know at this point that it is an alteration other than the pencil marks on each side of the cut out.??

Thanks Roy. I made sure to call it out in the report.

Its a lookout to support the end false rafter on gable end cornice. Its done all the time here.

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(It’s called a drop truss.)
That isn’t the way to install outlookers/outriggers.

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Not allowed. They make drop down gable end trusses where the top chord is lowered.

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Blocking, alone the wrong orientation, to prevent rotation. Its not the truss that has been modified. It’s stability to the truss farming that is arguable.

Thank you !
Now that was from an engineer.

Robert please put on your glasses.

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Once I can find them. Lol

Yes! :rofl:

Too much to call out.
Refer to SE and venting contractor.

What would they do about that screwed up truss modification.

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“Observed alterations to engineered roof trusses. Alterations appear to be field modifications performed during original construction. Recommend that the roof structure and the alterations be assessed by a licensed structural engineer.”

That’s the preferred wording for a recommendation on this. What happens after that is the engineer will do an assessment, look for a manufacturer’s stamp at the end of the truss, and call them. Highly unlikely that the original manufacturer is still in business, though, since there was a large consolidation of the industry in the 1990’s and 2000’s. If that’s the case, then the engineer will do a section strength reduction on the member, and see if there’s sufficient strength in the altered cord, and then make a recommendation for repair.

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