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New patio roof beam 7

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DoubleStud

Structural
Jul 6, 2022
453
What do you guys typically like to do if you are doing a new patio roof? So you have a ridge beam and two shoulder beams. Do you nest these beams inside the wall on a studpack all the way to the foundation with king stud each side? Or do you install a full studpack in the wall and connect the beam to the studpack using some kind of a hanger?

Screenshot_2024-04-09_092457_we9scb.png
 
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Ok, do studs to match the beam width and minium 1 king ea. stud and just screw it to the beam from both sides and hopefully the numbers work out? The 2 shoulder beams will be very close to the second floor diaphragm, but I dont think I can just strap. Would require the king studs to take bending and somehow transfer the load to the top plates. The ridge beam will be in the middle height of the upper wall so I need to make sure it can take bending if the ridge is pulling out.
 
DoubleStud said:
and hopefully the numbers work out?

Sort of? I do hope the numbers work out...but if they don't, I adjust accordingly. Additional kings, switching to steel...whatever it takes to feel good about telling them that, if built to my plans, they'll have a strong and reliable porch addition that meets or exceeds the requirements of the code.
 
phamENG said:
I'm pretty sure those hangers don't have any listed capacities for loads in that direction.

Maybe not. One may have to resort to actually doing calculations, or is our profession reduced to reviewing ESR reports and computer output?
 
When it comes to using manufactured components that have been tested, yes. I have no issues designing a custom bracket to do it, but when it comes to pre-made stuff I stick to the manufacturer's guidance. Especially Simpson. Given the scale of their operation, their ability to do this kind of testing, their obvious and unabashed profit motive, and the apparent ubiquity of this condition, if it was good for it I'm pretty sure they would have added that as a selling point by now. I'd also imagine that going outside of what a manufacturer has designed their product to do would fall below the standard of care.

Taking a quick look at the HUC hangers...they don't really publish the exact geometry but the CAD file is a decent guide. Looks like they're 16 gauge and the center of the fastener hole is about 7/8" from the concealed flanges. So you're barely allowed to consider shear at all per NDS as you're right at 3.5D for end distance (resulting in C[sub]Delta[/sub]=0.5 and really neutering the strength of the connection). So you get a few hundred pounds from that. But I'd bet the real weakness is in the 16 gauge material. The fasteners in the flange going into the supporting structure a little less than 1/2' from the inside face of the hanger. I don't think it'll take much to yield the 0.07" material in that bend. Maybe 70 or 80 lbs per fastener? And you only get about half of the fasteners due to the stagger. Then you have pullover, too. Not sure where that'll end up.

So even running some basic calcs, probably not good for more than a few hundred pounds. Diaphragm chord forces are likely to be a good deal higher than that. Seems prudent to just use hardware designed for the purpose.

 
Technically speaking, NDS doesn't enforce the 3.5D end distance as a requirement for nails. There are only recommended spacing, and end/edge distances in the commentary. Of course, that doesn't change the fact that this connection would have very little capacity to resist tension.
 
Eng16080 said:
Of course, that doesn't change the fact that this connection would have very little capacity to resist tension.
How much (tension capacity) would the OP need?
 
phamENG said:
So even running some basic calcs, probably not good for more than a few hundred pounds.

How much does the OP need in tension? A HUC46 is 14 ga, not 16. 4-10d are good for 750 lbs. Shouldn't need more than that. ASD loads shouldn't yield anything.

I'm sorry, but putting a hole in the wall and using an ECC seems to me to be a bad design (waterproofing), overkill and lazy.
 
SE2607, I was ready to disagree with you, but at least in terms of the nail capacity and using a rough estimation of the tension force, I think you're probably correct. I would also guess that the metal connector can probably resist that force, although I'm not too interested in running the calculation. It also seems that it probably wasn't designed to be used that way, which might or might not matter. Personally, I would still prefer a bearing type connection, but it looks like your method probably works too.
 
Not saying you need to use an ECC. But there are better ways than a light gauge hanger being pulled in a direction it was never intended to be used.

And the OP isn't asking for a specific case, he's asking about a general case. And yeah, if this is a little gable over a front door, sure. A few toe nails would work anywhere outside hurricane regions. But I don't get calls for those. I get called for for the 50'x60' screened and covered patios overlooking the ocean or the bay. A few hundred pounds doesn't even come close to working for a lot of chord connections I do.

And as for the nail comment. SE2607 was calling for SDS screws instead of nails. Those are 1/4" diameter and NDS does enforce it for anything 1/4" or larger. Though...an SDS screw wouldn't even fit in an HUC. The smaller #9 SD screws might, but they have a lot less capacity.
 
phamENG said:
I get called for for the 50'x60' screened and covered patios overlooking the ocean or the bay. A few hundred pounds doesn't even come close to working for a lot of chord connections I do.

That's a different animal altogether. My comments are related to the picture provided by the OP. One solution is not the correct one for all conditions. FWIW, I wouldn't use TNs for much of anything except to provide the minimum requirements for a "positive connection".
 
phamENG said:
The smaller #9 SD screws might, but they have a lot less capacity.

Thanks for making me go look that up. The #9 would have as much capacity as I would want to put in this type of connection.
 
I’m working on a similar entry canopy for a municipal building. For such a simple building element, it does present a lot of detailing challenges. With Zip-R becoming ubiquitous in my area, it’s even more complicated. Huber has a tech note recommending freestanding designs, since there is no code-compliant way to fasten hangers or ledgers through the foam layer (although I do see engineers specify those kind of details on a regular basis).

Architects really, really hate when you penetrate the Zip-R sheathing with a beam. It’s becoming a point of contention on every job now. Nevermind the lack of shear capacity…
 
That "code interpretation" from EdStainless is totally wrong.
 
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