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Block wood pieces holding joist to steel beam

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lubos1984

Structural
Jul 5, 2019
65
Hi all

I came across this during an inspection. Contractor should have packed a 2x10 and then joists no idea why he did it this way. Without having to rip everything out how would you evaluate this situation structurally and are any other remediations possible ?

Thanks again

Lu
 
 https://files.engineering.com/getfile.aspx?folder=b9f91e58-6135-49fc-8b41-1601ae55056b&file=160703A3-D7A8-4DFE-BE99-9DAC896C0D93.jpeg
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I've seen it done... but, would have rotated the blocking 90 degrees...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
Start by checking the fasteners in the blocking. How many? Full penetration?
 
No reason to rip everything down. If it can’t be justified by calcultion (which is a pretty straightforward check) then you could possibly pack under each piece, or alternatively bolt each piece through.

Its not a great detail. I guess the joists were ordered too short and this was one, albeit stupid, way to resolve it.
 
It looks like the third and fifth block from the right have split. The fourth may have split and the bottom piece removed. Drilling and bolting is out of the question as it would encourage more splitting.

Packing between each existing block and the steel flange would work if the packing was tight. If used, the grain should be vertical in the packing piece, but before commencing that work, it might be a good idea to check with the owner, who may be reluctant to accept such a Rube Goldberg solution. I know I would be.

BA
 
Lubos1984:
Some contractors don’t have the vaguest idea what they are doing, why they are doing it, or how it works. I’ll bet this guy doesn’t even have a license to operate a nail gun or a circle saw, in public, let alone a GC license. He should be made to cut some more length off those 2x? joists and see if they are still too short. How is the long 2x? packing fixed to the stl. bm? I see what might be a single bolt through the stl. bm. web, way over on the right in the photo. Is that packing really bearing on the stl. bm. flgs? The joist hangers may be o.k. if fully nailed properly, but they seem to be splitting some of the small end blocks, and those nails are probably not long enough to penetrate into the bigger stl. bm. packing. Thus, the jst. end reactions would be limited to the small end block nailing into the bigger stl. bm. packing, with due regard for splitting potential.

If the nailing in the jst. hangers and into the small end blocks is o.k., so that the jst. hanger cap’y. is o.k., I would do something like the following. I would cut a bunch of 12” long, 2x2 stl. angles, and shove them up under the small end blocks, almost lifting the blocks a little, to tighten or minimize splitting potential. I would pre-drill the vert. leg of the angles, which points downward, for 4, 5 or 6 structural screws, with a tight fit on the screw shank. These screw holes should be staggered so as not to split the stl. bm. packing. Pre-drill the screw holes in the stl. bm. packing, and the packing must be bearing on the stl. bm. flg. or you shouldn’t be loading it that near it bot. edge, for fear of cross grain tension, etc.
 
Better yet, chisel off the bottoms of the filler blocks, and put the steel angles right up tight against the joists.
 
If the existing math doesn't work, then I like SW Composites idea. you could get a long angle and lag bolt it to the beam. You'll have to drill through the W section though.
 
Seems fair to go to that contractor's house and have someone do the same to it. If they object to that idea then a lot of money needs to be extracted from his wallet.
 
Except, now you have likely chiseled away several nails in the end blocks and their existing shear strength. Also, you need a 3x3 angle or larger, and the reaction is imparting a larger canti. moment, at about 2 or 3”, on the angle and a larger prying action on the screws. A continuous angle may have to be pressed up to support some jst. hangers, which may not all be perfectly in line. Also, the 2x packing should be regularly bolted through the WF beam in any case, not just bearing on the bot. flg. It’s a really crappy condition and detail in any case, but the jst. hanger is really only connected to the end blocks, and then through them and their nailing, to the WF packing. So, my thought was that if the jst. hangers were properly nailed to the end blocks, without any cracking or splitting, then support the random height end blocks. Someone who can look at the worst end block and hanger nailing conditions has to make this call, we can’t from that one photo.
 
Step 1: Ask to see the drawing the engineer came up with. (Doubt he has one.)

Step 2: Check all the math. (Pretty straightforward.)

Step 3: Give the contractor a piece of your mind.

Step 4: Make him replace every single one of those stupid split-waiting-to-happen spacer blocks with an LVL plate, screwed to the face of the beam packing with structural screws. It could be one long LVL plate, but I'd make him work for his error.
 
Nail a 2x4 ledger under the blocks (and shim) and call it a day. Shitty detail for sure, but I doubt there is a whole lot of load there given the joists' apparent size.
 
XR said:
given the joists' apparent size.
Appear to be 2x10s to my eye, that's not nothing. Maybe 2x8 now that I look closer.

I also feel that their mid-span solid blocking of the joists in the next bay is quite suspect as well.
 
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