Floor Joist Or Not?

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A/A Fuel GTX

A/A Fuel GTX

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WI & AZ
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Electrician
Does the photo show a floor joist that is drillable both horizontally and vertically? Not sure if it's considered a joist or some other structural member.IMG-81.jpg
 
Agreed, probably considered a cripple wall. The gusset plates make it look like a prefabricated/engineered wall, similar to a truss design, the GC would be wise to check with the engineer for any major modifications. Subject to the same requirements as any other wall, not an issue so much for electricians, plumbers could run into issues...
 
That's basically a spacer joist (cripple is correct) the same height as the rest of the joists, but built for vertical strength without the need to span open space, so there are no diagonal members. Similar to a gable end wall for a truss-built roof.

There should be no issue with standard drilling vertically or horizontally.
 
It's a floor truss.

Functionally there is no problem with drilling because it's sitting on top of the foundation instead of spanning, but an inspector could take issue with it
 
Joe.B said:
The gusset plates make it look like a prefabricated/engineered wall, similar to a truss design . . .
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If I'm not mistaken, the next joist is an I-truss. Two 2x3s with a particle-board web. You can just see the glue joint.
 
James L said:
It's a floor truss.

Functionally there is no problem with drilling because it's sitting on top of the foundation instead of spanning, but an inspector could take issue with it
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I would not call it a truss, specifically because it is not spanning anything. There is absolutely no need for stiffness or shear strength.
It is a short wall.
In earthquake areas it may be necessary to add shear paneling to it, but that would make it a shear wall, not a truss.
 
GoldDigger said:
I would not call it a truss, specifically because it is not spanning anything. There is absolutely no need for stiffness or shear strength.
It is a short wall.
In earthquake areas it may be necessary to add shear paneling to it, but that would make it a shear wall, not a truss.
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I agrre about the span, and almost mentioned that specifically. You're probably right as to what it's called technically.

Like I said, functionally there's not an issue. But considering the gusset plates, I would be leary about drilling the vertical pieces so as not to make an inspector go "hmmm"

I'm actually wiring a house right now with floor trusses and that same rim, and I drilled the studs above for that very reason.
 
I know this has nothing to do with the OP.
Is it common to rough in partitions directly on the dirt in your area?
I've never seen that done before except for DIY's.
Feel free to correct me if that's not what I am seeing.
 
Knuckle Dragger said:
I know this has nothing to do with the OP.
Is it common to rough in partitions directly on the dirt in your area?
I've never seen that done before except for DIY's.
Feel free to correct me if that's not what I am seeing.
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I see what looks like concrete footers under each partition when I blow up image, a lot of dirt around and on them though. Surprised that there wasn't a full pour done, or any vapor barrier put down. Around here would have all sorts of moisture issues and then mold.

To the OP is there a reason you want to drill thru the Jack wall, instead of running in between the joists parallel to the wall? Wall likely load barring given it sits on the footer, but as already suggested strategically drilling for wire placement shouldn't compromise the load barring (do that everytime we drill thru an exterior wall) unless contractor used undersized or bare minimum load capacity components compared to engineering specifications. But if concerned reach out to the engineers that designed the structure for confirmation and limitations.
 
Knuckle Dragger said:
I know this has nothing to do with the OP.
Is it common to rough in partitions directly on the dirt in your area?
I've never seen that done before except for DIY's.
Feel free to correct me if that's not what I am seeing.
Click to expand...
Those partition walls you see in the basement are on concrete footings.
 
Fred B said:
I see what looks like concrete footers under each partition when I blow up image, a lot of dirt around and on them though. Surprised that there wasn't a full pour done, or any vapor barrier put down. Around here would have all sorts of moisture issues and then mold.

To the OP is there a reason you want to drill thru the Jack wall, instead of running in between the joists parallel to the wall? Wall likely load barring given it sits on the footer, but as already suggested strategically drilling for wire placement shouldn't compromise the load barring (do that everytime we drill thru an exterior wall) unless contractor used undersized or bare minimum load capacity components compared to engineering specifications. But if concerned reach out to the engineers that designed the structure for confirmation and limitations.
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I agree with you but the location of the service on this house leaves me no choice but to drill the Jack wall to run the SEU from the meter to the panel in the basement.
 
A/A Fuel GTX said:
Those partition walls you see in the basement are on concrete footings.
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Got it.
I missed it.
I've never seen it done like that on professional settings, for the reasons that FredB mentioned.
When in doubt I always ask the GC. Typically it's over engineered but sometimes the GC doesn't want us to touch it.
 
Not unusual to pour the basement floor later in the job around here. I like them poured just after the under slab plumbing is finished. So I don't have to work on mud! ;)

I agree, that wall is too close to the dirt for my location. But I see wooden foundations in the IRC. Around here they like 6 inches for termite protection.
 
That is a ladder truss.
Or a “gable end floor truss”
I would treat it as any other truss and make sure drilling is acceptable beforehand.


R802.10.4 Alterations to trusses. Truss members shall not
be cut, notched, drilled, spliced or otherwise altered in any
way without the approval of a registered design professional.
 
Hv&Lv said:
That is a ladder truss.
Or a “gable end truss”
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That's the construction, but it's not being used as a beam element, it's being used as a wall. So while I agree that it is worth checking with the designer, it should be OK to treat the same as any wall.

Cheers, Wayne
 
wwhitney said:
That's the construction, but it's not being used as a beam element, it's being used as a wall. So while I agree that it is worth checking with the designer, it should be OK to treat the same as any wall.

Cheers, Wayne
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All gable end floor trusses I have installed are essentially “walls”.
They are still part of an engineered system.

Ive seen them drilled and notched before like any wall.
They are generally built in the factory to save time on the job.
Keeps the framing crew from having to build the starting wall.

Still, there may be inspectors that say no, simply because it’s part of a system.

How many of us have drilled something only to later realize we wished we had just asked first.
 
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