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Cathedral Roof, Gable Wall Framing 3

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Skinnattittar

Civil/Environmental
Jul 23, 2015
23
Hopefully this has not been asked too many times on these forums, but I have a gable wall on a building with a cathedral ceiling (see pic) where the framer did not make the studs full height.

IMG_20210405_115610303_s9wolc.jpg


Our plans do not specifically call out the requirement that the studs be full height and the contractor is saying it is our fault for not tell them and their framers that they could not build this wall the way they did. Our general notes do not specifically address this sort of issue, but do call out that the project is to be built in accordance with IBC 2015 and NDS 2015 with an additional note "... all framing shall be plumb, true, and adequately braced such that the structure is rigid..." (not my choice, but I'm not in charge here...).

I've only done some google searches, but I'm not finding anything explicit in either that dictate full height studs or bracing the wall (though I feel like I have in the past...). I've flipped through my construction guidebooks and some googling, and the only time this sort of detail is addressed (as it is shown in the pic) is to say "don't do this" but I don't see a reference to any code. So my question is; is there?
 
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Must not be a very experienced crew if they did that. I'd bet the wall is pretty flimsy relying on a non-continuous double top plate to span that entire wall as a girt.

I can't speak to a specific code clause, but all loads must be adequately supported, and this doesn't adequately support the wall for the wind loads. Did your drawings not cut a section through there to show how the gable end was intended on being framed?
 
Yeah, I'd also tag this an error of design/specification. Given the opening size, the only full height studs that were going to do you any good were probably the jamb studs on either side of the penetrations. You might be able to retrofit those into being full height studs with some extra bits, metal straps etc. I'm not really a strong believer in the performance of those setups but this is kind of a hail Mary situation.
 
I would also agree with Koot that you were in for a battle anyway if you didn't specifically detail out this wall. For an opening that large, your wind posts (king studs) should have been pretty substantial. Based on the picture, I'm only seeing 2 "king" studs which I put in quotes because they don't actually go full height.

Regardless, you're going to need to fix it, and that may unfortunately require dismantling the wall. Could you basterdize and piecemeal in the right stuff, sure, but it will look like a dog's breakfast. If the exterior finishes are not in place yet, I'd just tear it down and re-build it. Pay close attention to the wind posts at each side of the opening as well as the sill plate (wind girt) at the top of the door opening as it still needs to be able to span horizontally to the wind posts and you don't want it to be too flexible.
 
KootK said:
Yeah, I'd also tag this an error of design/specification...

I analyzed the studs as fully height, and they needed to be 2x8@16"o.c. and they worked fine (and were called out on the plans), but were intended to be full height (which I had assumed was the expectation as that's what all my design guides show/describe).

KootK said:
...Given the opening size, the only full height studs that were going to do you any good were probably the jamb studs on either side of the penetrations...

We called out for two (2) jack studs to support the header, and four (4) LVL king studs to brace the opening. This will have a roller door attached the jamb, so the king studs will be taking the load of the door panels and the header at its height.

KootK said:
...You might be able to retrofit those into being full height studs with some extra bits, metal straps etc...

My repair proposal will be to add two (2) lvl king studs. This will be enough for strength, but on their own would be quite springy. All those extra king/jacks should stiffen that up quite a bit, though.

KootK said:
...I'm not really a strong believer in the performance of those setups but this is kind of a hail Mary situation.

You and me, both. My suggestion had been just to tear out all the incorrect framing and build it back in correctly. They're still at the plywood phase, with no additional hardware or exterior work added. All equipment (scaffolding, cranes, cherry pickers, lulls, etc...) is still on site. Maybe a couple days for a small crew? And it will look cleaner and neater, probably be cheaper overall...

jayrod12 said:
Must not be a very experienced crew if they did that. I'd bet the wall is pretty flimsy relying on a non-continuous double top plate to span that entire wall as a girt.

Unfortunately, the state I work in does not have any certification or licensing requirements to advertise yourself as a builder. Having a contractor is primarily about insurance than competency. You wouldn't believe the questions that get raised or finger pointing about project expectations...

jayrod12 said:
I can't speak to a specific code clause, but all loads must be adequately supported, and this doesn't adequately support the wall for the wind loads. Did your drawings not cut a section through there to show how the gable end was intended on being framed?

That's all that I've come up with so far is that it be designed properly. I will be trying to convince the boss to add notes about following some more specific guidelines for our builders, like the WFCM, to cover our asses for all the minor details that are impractical to try and describe in the single page of construction notes that my boss wants us to stick to.

Yes, there is a section, and it does show the plate at a higher level than the bottom-of-trusses/top-of-wall, but it is not called out specifically.
 
I agree with the above that this is a pickle. Best of luck on getting it resolved. One suggestion that might help, if you have a good relationship with the architect sometimes you can add notes or details to their sheets to clarify some of the final points of the design. I find that they generally end up having elevation views for all sides of the building along with wall section cuts. I have found it useful to take advantage of these elevations for things just like this detail.
 
If there's a section showing the top of wall plate being above the trusses, then the argument as to whether you showed it well enough on the drawings is clear. And if it wasn't clear based on the information provided, a simple RFI would have solved it. So why you are in the mess could be attributed to the contractor based on the information at hand. However, that's a moot point since here you are having to fix it anyway.

I really think dismantling and re-building is the proper way to go. But you could give them the two options, re-frame or reinforce, and let them decide what path they would prefer to do.
 
You do not appear to be at fault as far as the balloon versus platform framing goes, however, I am curious how you intended to get the point loads from the king studs into the ceiling diaphragm. That is a tall and wide wall!
Seems a detail would be needed for that which may have mitigated the issue altogether.
 
Nice! I'm not sure that I'd show that to the contractor though unless this has become a legal matter. I feel that the odds are high that you'd just annoy the bejeezus out of them by implying that you expect them to read the IRC.
 
I would focus on determining a reasonable solution that does not involve re-framing the wall. Going down the other rabbit hole will be very counterproductive and could yield the opposite result you want.
 
For what its' worth, I love how your photo makes the paper looked like an overhead door partially rolled up.
 
jayrod12 said:
If there's a section showing the top of wall plate being above the trusses, then the argument as to whether you showed it well enough on the drawings is clear. And if it wasn't clear based on the information provided, a simple RFI would have solved it. So why you are in the mess could be attributed to the contractor based on the information at hand. However, that's a moot point since here you are having to fix it anyway.

I really think dismantling and re-building is the proper way to go. But you could give them the two options, re-frame or reinforce, and let them decide what path they would prefer to do.

I would say the section showing the top plate as elevated was not super clear, but the issue is whether or not it needs to be. Is there anything in the IBC or NDS that instructs or suggests that studs have to be the full height of the wall and/or properly braced unless an exception is directly noted? For instance, say the project requires a 10ft tall wall (not too uncommon these days). Is there anything in the code that would stop a contractor from scabbing 8ft studs together to built to the wall to 10ft, or built a 2ft stub wall with an 8ft wall on top? Obviously if it is spelled out on the plans, then we're covered, but could an engineer be held at fault for not specifying what is, let us admit, an obvious standard to built walls to their full height with continuous studs (unless noted or excepted otherwise)?

XR250 said:
From the 2018 IRC...

Cool! Unfortunately that is in the IRC and not in the IBC, but almost the exact same thing is in IBC 2015 2308.5.1! Which is exactly what I am looking for! Thank you!

XR250 said:
You do not appear to be at fault as far as the balloon versus platform framing goes, however, I am curious how you intended to get the point loads from the king studs into the ceiling diaphragm. That is a tall and wide wall!
Seems a detail would be needed for that which may have mitigated the issue altogether.

Oh, there's PLENTY missing of what they didn't do on this part of the project... But the full height wall studs is something they are very much pushing back on and trying to blame us for.

KootK said:
Nice! I'm not sure that I'd show that to the contractor though unless this has become a legal matter. I feel that the odds are high that you'd just annoy the bejeezus out of them by implying that you expect them to read the IRC.

Oh, they have already tried to weaponize the IBC/IRC against folks, and have questioned us several times about details we included with "I don't think we need to do that, that's not in the code". Basically, whenever they want to justify something extra they did (and get paid for it) they say it was per code, and whenever they DIDN'T do something they were supposed to (and get paid for doing it anyway), they say it wasn't required per code...

Brad805 said:
I would focus on determining a reasonable solution that does not involve re-framing the wall. Going down the other rabbit hole will be very counterproductive and could yield the opposite result you want.

That's what we're working on ATM, but the contractor is trying to avoid having to do the repairs by saying it wasn't necessary to begin with.
 
I typically try to work with the contractor in situations like these, and not let the situation become "us versus them."

Are there inexpensive solutions acceptable to you, the contractor, and the owner? For example:
* Diagonal braces from the top plate to the roof diaphragm (won't look great, but depending on the use of the space, may be acceptable)
* A continuous steel member (girt) spanning the entire width of the building, lag screwed to the top plate (I am thinking a steel angle)

DaveAtkins
 
I looked at your photo again. Most of the lateral load goes to the king studs; very little goes to the studs on either side of the door opening. And the studs on either side of the door opening span to the top plate which is very close to the corner of the building.

So the essence of the problem is making the king stud a continuous member. You could tear out that portion of the wall and make the king stud continuous. Or you could use steel splice plates to create continuity. Structural steel, not light gauge straps.

DaveAtkins
 
Looks like it would be easy enough to cur thru the top plate with some full height sisters on the king studs. I'll ask this question again, however. "How are you going to get the point loads from the king studs distributed into the ceiling diaphragm?"
 
XR250 said:
...How are you going to get the point loads from the king studs distributed into the ceiling diaphragm?

We developed a connection detail to an on-the-flat plank in the ceiling system along the interior "rake" line that will act as a beam or distribution plank to a series of drag/compression struts to the bottom of the roof trusses. We included this to the fabricator and it appears to be included in their calc sheets. They're a messy packet of DOS lines but I spoke with the rep and they pointed out the code lines that include this in their design. They have an engineer who stamped the packet and I'm willing to accept them as competent, and the trusses appear pretty beefy to me, but I'm not a timber truss expert so take that for what its worth. And yes, I designed the walls as shear walls along with the connections to the trusses, foundation, and nailing patterns, and most of the hold downs are already installed. This had been an impromptu inspection of this building, so all the work had not yet been completed.
 
UPDATE: I designed a repair detail of microllam king studs to go through the plates and a series of connection details for the multitude of "headers". In the other walls that had a similar issue, I added intermittently spaced, full height king studs and connection details. The primary connections are mostly the same as they originally had been intended, the new secondary connections are all possible with a normal nail gun or maybe the need for a palm nailer where space might be more limited. Unfortunately, the contractor has not been impressed and wants to do "a happy medium". They have requested a site visit to discuss.
 
Not sure what kind of contract you have in place, but I usually find that sending a fee proposal for the visit or informing the contractor/owner of the cost of the visit and reminding them that designing the repair is an extra, hourly cost, makes the "need" for the site visit magically go away and things get done. Once they realize my services aren't free, they see the value in just doing the job right the first time. Good luck!
 
It sounds like your option is the 'happy medium', considering that the full fix is tear it out and replace it fully.
Pointing out to the owner that this guy is causing delay and adding costs should get it moving.

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