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Repairing improper LVL installation

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jplay2519

Structural
Oct 7, 2014
100
I have a LVL that is supporting 1st floor, bearing wall of 2nd floor and vaulted ceiling. The beam is 3-ply and was nailed together insufficiently so the outside ply is separating and the beam has also rotated making the joist hangers pull out and the joists are not properly supported. The posts are (5) 2x6 stud packs (which are insufficiently attached to each other and are separating due to buckling), the posts were not cut to the correct length so there are (2) 2x shims that the beams are resting on and are being crushed.

I am going to check the LVL to ensure it's sufficient for load, which I assume that it is, but my question is if I want them to keep the beam do you think it can rotated back into place? I want them to shore the beam, remove the posts, set the beam aright, install solid 6x6 (or whatever I calculate as sufficient) with post caps, reattach I-joists/hangers.

One photo is taken looking at the beam from directly below so that you can see the nail pulling out and the joist hanger pulling away.
 
 https://files.engineering.com/getfile.aspx?folder=cee0abdc-e851-404b-b6f3-dba6aecefd84&file=20180518_073129.jpg
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I'd have normally used adhesive in combining the laminations... that said, I think the only manner in which you can 'pull' the lams together is to use a series of bolts, maybe top and bottom and slowly tighten them to pull the laminations together.

Dik
 
Looks like the floor sheathing changes direction on top of the LVL. That, and possible shrinkage of the floor sheathing or overall building has likely caused or contributed to the separation. As dik stated, bolts are likely the best fix.
 
If the plies are "nailed together insufficiently" as you say, or not at all, then I suspect the problem (the separation of the plies) is due to the outer ply being overloaded as a result of the one sided loading from the floor joists. If you can remove the load from the floor joists by jacking the floor joists, then the outer ply might "relax" back into place, or it might need a little help by sucking the plies together with screws. Personally, I would not attempt to pull the plies together with fasteners (screws or bolts) without first removing, or at least reducing, the side load from the floor joists, but it might work with the load present.
 
...agree about reducing the load; screws will not likely be sufficient to pull the laminations together.

Dik
 
Thanks guys. Bolts are going to be my choice of attachment. I thought about supporting the beam but not the joists, I'll inform them to make a temp wall at both levels to reduce the load on the beam and hopefully that reduces it enough to get the laminations "loose" enough to pull together and get everything connected. It won't be perfect but it will prevent further damage and it will properly support the load. Thanks for helping me think through this, sometimes the solution can be thought up but I'm not always sure on the constructability of it.
 
jplay;

I would also explore the potential longitudinal shrinkage issue of the subfloor/i-joists that I mentioned. I have seen this occur in the field on multiple occasions. If it is shrinkage, it will be difficult or impossible to pull everything together.
 
I would shore everything except the LVL. Remove all of its load and isolate it, then start the repair process. Agree with dik that thru-bolts should be used to pull the plies back together, but you also need to fully understand why they were pulled apart. Shrinkage, as XR250 notes, is a likely contributing factor. Not sure what the staining on the I-joists is, but they might have been wet when installed. The first joist hanger shows pulling at the bottom.

The joist hangers are inadequately nailed as well.
 
XR250, Ron

The shrinkage damage would be from the perpendicular sheathing being attached to the first two plies and then the parallel sheathing being applied to the last ply and thus pulling them apart? I like to just ask through my understanding of the issue instead of just assuming I know what you mean.

Ron the joist hangers in some places have nails so close to the bottom that they just split the LVL, I think many of these issues are due to improper installation, so then the loading, shrinkage, etc are really taking a toll on the structure. I have a question about the wall above, I know I can shore the loads resting on the wall but the actual wall itself, there isn't really a way to relieve that dead load is it, unless you do a needle beam type situation where you have a shoring wall on each side then "joists" between and attach the "joists" to the studs. I've never really tried to support a wall except providing a wall or beam directly below.
 
Chiming in here with a different opinion:

This is a new building under construction, isn't it? I'm gathering this from the way the failure is happening.

Look at the frost wall, how its buckled. I might be wrong but it looks like they installed the frost wall before they threw up the floor platform above. The triple LVL was meant to bear on concrete, but they framed the frost wall too tall. the top plate of the frost wall then supported the 3xLVL until it was loaded, and then she rolled over.

It looks like you have a couple real rookie framers here. I agree with the bolting fix. You're right, keep an eye on the joists bearing on that 3 ply. I might also be concerned about the state of the floor sheathing above once you start reefing on the floor platform framing above - you might be left with popped nails or ripped sheathing around the nail heads, if that concerns you.
 
Is there a space at the top of the LVL pack? If so, shrinkage within the entire structure my be such than 'sucking' everything back together may be impossible. After determining the original beam pack was sufficient) I have :
A) Provided support to everything, in-so-far as is possible.
B) Using reciprocating saw, cut out all nailing between the pulled LVL & the rest of the pack.
C) Inserted a Plywood member in the spaced, sized on the smallest space width (may be tapered along the width)
D) Apply the fasteners of choice, with the possibility of also using a glue which has value, even when thick.
E) Consider possibility of original framers using their foreheads as hammers.
 
Weyerhaeuser's LVL information has tables for how to connect top and side-loaded LVL beams made of multiple plies.
Download manual from: See tables on pages 14 and 15.

How the GC gets the plies together is usually considered 'means and methods' of construction.
I would specify for the plies to be tightened up, and call out the connection based on the side loaded table.

Eric McDonald, PE
McDonald Structural Engineering, PLLC
 
McSEpllc said:
How the GC gets the plies together is usually considered 'means and methods' of construction.

Eric,

I disagree with that in this particular case. Until the cause of the separation has been determined (shrinkage etc.) , the GC may cause more problems without proper direction from the SE.
 
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