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More Engineered Beam Issues? 1

XR250

Structural
Jan 30, 2013
5,510
This is an 8 ft. span, 3 1/2x9 1/4 beam in the crawlspace of a 2 year old home. It supports 12 ft. trib of floor framing (trussed roof). There are some cracks in the sheetrock near this beam.
1) What material is this? It looks like crap. It appears to be one 3 1/2" wide ply. Kinda looks like an LVL. Could it be LSL? It has no markings.
2) The beam appears to have slight sagging in each span. I did not have a stringline with me, however.
3) It also appears to be crushed slightly at the edge of each support.


No way this should be sagging at this span with only 12 ft. of mostly floor dead load.
My guess is that it was put up soaking wet which temporarily weakened it and it has shrunk a bit as well.
The owner states the cracks have not worsened in a year.

Thoughts?

1737403531363.png
 
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I've seen solid, but tract builders don't seem to know what grout is. I'm not being hyperbolic. The typical responses are "you mean concrete?" or "we're not settin' tile here!" So when I see a standard block at the top of the pier, my assumption is that it's hollow until proven otherwise.
 
Oh, I have no expectation that it is anything but runny mortar. Same goes for custom builders in my area though.
Never seen a "punch thru" issue however.
 
Whats with the cutting down to size of those cross beams?

They all look like they've been badly sawn down for some reason. Sawn in half lengthways?
 
You mean the floor joists? Those are wood I-joists. Nothing was cut down to size there.
 
It was this bit which looked cut to me.

Very rough edges and a notch in more than one joist?

Screenshot 2025-01-21 181941.png
 
I thought so too but it appears to be a solid 3 1/2" wide - something I have never seen in an LVL.
There are some wider LVL's out there.

I thought so too but it appears to be a solid 3 1/2" wide - something I have never seen in an LVL.
That's almost certainly a PSL. LVL would have straight lines on the bottom where the veneers are glued together. The photo from XR shows strands.

And that coloring is very typical of aged PSL beams.
 
Another thought or 2 to add -

The crushing at the support puzzled me. I'm wondering if the builder maybe used a machine to set a bunk of plywood on that area. Or maybe wall framing material after the subfloor was on. That would explain the crushing.

If the LVL was soaking wet when the house was built, it may have slowly dried out and shrunk. (They change a lot in size with changes in moisture) That would explain the drywall cracks, as you mentioned in the OP.
 
@XR250 they're required by code here so it's hard for me to put myself in the mindsight of not connecting them. It's just basic good practice here to connect abutting things together, particularly if A relies on B for support.

From an earthquake perspective (where everything gets moved) nominal connections do a huge amount of hidden lifting to keep things together and behaving as a building.

In a non-seismic region I'd say at least it would help with long-term movements? It keeps the pile tight to the bearer and prevents them separating (bouncy or squeaky floor).
 

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