Truss Failure

[XR250]

This guy thought it was a good idea to store a bunch of angle iron in his attic. Happened to every truss.

 

[SWComposites]

Well, just jack it up and nail on a bunch of plywood gusset plates.

 

[XR250]

That is what they are going to do.
I'm staying away from this as I feel every plate on every truss joint should be inspected and I don't have the attention span for that.

 

[SWComposites]

I’m not too impressed by those truss plates. Looks like they were attached with some (inadequate) glue.

 

[XR250]

No glue - they are pressed on nail plates - like most trusses.

 

[LittleInch]

Doesn't look like they pressed hard enough then....

Has the plate come off intact or have all the "nails" sheared off?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[XR250]

I haven't seen them but is my understanding that the plates just peeled off

 

[phamENG]

Looks like pressed plate not nailed plate. And yeah, storing a bunch of steel in your attic is likely to overload those plates. The tabs are small enough that they'd definitely pull out before they sheared/ripped off the plate.

Yikes.

 

[LittleInch]

Was there any evidence of differential movement in shear? between the roof structure and the attic floor. That scrabbled tearing on the top surface looks quite odd, as though the plate sprung from the bottom surface before finally giving way / springing off. Guess we won't know what happened once the first one went

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[DoubleStud]

So did the bottom chord fail? Pretty crazy if it was still supporting the load in the attic. Maybe interior non load bearing wall came to the rescue.

 

[RontheRedneck]

Fascinating.

When truss plates are overloaded they typically curl and pull out. I've never seen one come out as cleanly as that one. Usually they pull some chunks of wood out with them.

I agree that every plate should be checked. Especially at the heels.

Do you have any more pics or information? I'd love to know more about it.

 

[Brad805]

Old truss plates were a lot smaller than they are now. I cringe when I go up into the attic of my 70's vintage house.

 

[phamENG]

Ron - look at the truss in the background. Looks like there are some chunks missing there.

While you're here, you should take a look at this thread if you want your blood pressure to rise a little: thread784-509998

 

[IRstuff]

One thing that you won't know for sure is how much deflection occurred with the walls on either side of the trusses since the roof load is no longer directed fully downward by the trusses. This could mean that jacking the up trusses wouldn't necessarily restore everything to the as-built configuration.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

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