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New patio roof beam
7

New patio roof beam

New patio roof beam

(OP)
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?

RE: New patio roof beam

2
I use a bearing connection on the stud pack/post. I like to use bearing connections instead of side connections like hangers whenever possible. It's better structurally because of a direct, reliable load path. It also shouldn't be too difficult if you're using platform framing. It's also why I try to avoid balloon framing on principle.

When I use hangers or clips, it's because I don't really have a choice (like beam-beam or beam-joist connection).

RE: New patio roof beam

(OP)
OK, I was just wondering maybe it is better to totally separate the structure.

RE: New patio roof beam

My approach is the same as milkshakelake. I always prefer a direct bearing connection. It will perform better long term and is less error prone and easier to construct.

If it wasn't for architects needing to hide every beam within the floor on these projects, I would use drop beams everywhere for floor framing rather than a million joist hangers. (Of course, then I'd lose all the supposed money and free vacations these builders are convinced Simpson is giving me in commission!)

RE: New patio roof beam

Quote:

OK, I was just wondering maybe it is better to totally separate the structure.

Clip angle or hanger connection from the side is not separating it, even if using a ledger. A separated porch with its own lateral system (i.e. some bracing) and some physical separation might be what you're talking about, but I don't really see the need for that. I don't see what you would gain. Maybe seismic gap, or better ability to insulate the building envelope? Those are valid, but it seems like overkill.


Quote:

Of course, then I'd lose all the supposed money and free vacations these builders are convinced Simpson is giving me in commission!

Wait, you're not getting that money?

About dropped beams, one issue is blocking. It adds cost and complexity compared to hangers, even if it's a more reliable load path. The other issue, which is not that major, is that hangers are better for torsionally restraining both the top and bottom of the beam. So I'm not sure I agree 100% about the dropped beam thing. Of course, the bottom of the dropped beam is generally in tension, so I'm not worried too much. I'd just rather have that additional restraint than not have it.

RE: New patio roof beam

Here in WI this would be free standing.
Since if it attached to the house it would need to meet the code requirements for a house, including foundation.
Decks and patio roofs usually built separate and to a lower standard.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

RE: New patio roof beam

I like to use bearing over columns as well but for your extended roof you need to pay attention to lateral forces as well.
If you run a stud pack up to the bottom of your new beams, what keeps the entire roof system from pulling away from the house?
You need to ensure that there is a horizontal load path that can take this load into the house floor and roof diaphragms.

For your porch roof - the roof appears to be simply cantilevered out from the house with no other lateral bracing system.
This means that, as the new roof gets loaded laterally, the new eave beams will want to push and/or pull in a direction perpendicular to the exterior wall of the house.

A stud pack spanning from floor to floor, with adequate connections top and bottom is one method.

RE: New patio roof beam

I've been specifying concealed flange hangers recently. Don't have to interrupt shearwall chords or corner studs, and for existing structures where you know where the studs are, you don't have to have to tear into the wall.

RE: New patio roof beam

milkshakelake, those are all good points concerning the dropped beam. I was exaggerating slightly saying I'd use them everywhere. My typical detail involves solid blocking over the beam and some type of connection between the joists and beam, usually hurricane ties. The biggest downside is probably the lack of bracing at the bottom of the beam as you mention, although obviously it's not an issue if the beam is simply supported. The negatives of the flush framed condition are a less reliable connection, possible torsion on the beam, and possible differential shrinkage between the joist and beam (like in the case of sawn lumber joists supported by an LVL).

I agree with JAEs comment. You should have a load path anchoring the roof into the building, kind of similar to an exterior deck.

RE: New patio roof beam

On top of studpack, w/ Simpson caps. Usually the ECC family

RE: New patio roof beam

The one I designed and built for myself is free standing. But then, I like columns.

RE: New patio roof beam

I guess I disagree with the consensus. I would rather put a side load hanger, designing the post for the eccentricity than poke a hole in the wall. I know it's easier to design a concentrically loaded post and throw a "standard" detail on the plans, but I don't think that's the best detail nor do I think it's easier to build.

Just my two cents.

RE: New patio roof beam

Quote (JStructsteel)

On top of studpack, w/ Simpson caps. Usually the ECC family

A Simpson ECCQ44 is almost $90. A Simpson EPC4Z is about $25.00.

RE: New patio roof beam

(OP)
JAE, correct. To be honest, that’s why I asked this question. If I nest it, 4 of the stud pack isnt really taking the lateral load, who knows how many king studs I need. But if I connect it with a hanger, all studs will span from diaphragm to diaphragm. But now I need to make sure the hanger can take the axial pulling load. I just want to know what’s best before I start detailing and run numbers. If I put it inside wall, and I have enough king studs to transfer the load, how do I connect it to make sure it doesn’t pull out?

RE: New patio roof beam

Quote (DoubleStud)

If I put it inside wall, and I have enough king studs to transfer the load, how do I connect it to make sure it doesn’t pull out?

To install the king studs, the interior sheathing probably needs to be removed and perhaps some of the exterior sheathing around the beam penetration to allow the new studs to be installed.

The connection at the base would typically be steel angle brackets (Simpson has some) that would nail to the floor sill plate perhaps - then chase down to the diaphragm with extra nails.

At the top it depends on the floor framing above (joist orientation) but some means of strapping to floor joists or to the floor sheathing with blocking and straps might be necessary.

RE: New patio roof beam

For the ridge and shoulder beams, as already discussed above, I think I would use direct bearing, although there are plenty of good arguments for the alternative.

For lateral loads, I'll typically rely on a ledger along the roof profile connected with wood screws into the center of each wall stud. The roof sheathing is nailed to the ledger with nails at 6" or 4" o.c. For roofs which aren't too large, this should be adequate to resist the lateral forces from the roof. For larger roofs or where the lateral loads are more significant, I might add hold-down connectors which are ideally anchored into the floor. In this case, I would expect there to be a location where each ledger crosses the floor framing, and that's where I might add a hold-down (if it's needed).

RE: New patio roof beam

Even for small roofs, the horizontal load on the two eve beams could be substantial. Specially, when you consider the fact that an open patio many times is closed off with screens or windows, which would increase the lateral load on the porch.

RE: New patio roof beam

Quote (DoubleStud)

how do I connect it to make sure it doesn’t pull out?

You can use SDS screws instead of nails to connect the face mount HUC hanger to the post.

RE: New patio roof beam

SDS screws are great, but I'm pretty sure those hangers don't have any listed capacities for loads in that direction.

RE: New patio roof beam

2
I prefer a bearing pocket with full height studs on both sides for 1) stability at bearing and 2) resisting out of plane forces on the wall from the diaphragm chords of the porch roof. If I can get tension ties into a floor diaphragm (like the standard deck detail) I'll try for it, but sometimes that can leave you with an unacceptable aspect ratio in the porch roof diaphragm. And sometimes it's a great room with 20ft ceilings.

If it requires work inside, it requires work inside. As long as they don't have 200 year old horse hair plaster walls, it's almost always easier to make changes to the interior finish (though occasionally they are stripping the exterior to do a brick or stone veneer inside the porch). I have done some that act as independent structures, but when they see the cost of columns and foundations or the bracing/wall segments they have to add, they often relent and let the contractor cut some holes in the living room.

RE: New patio roof beam

(OP)
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.

RE: New patio roof beam

Quote (DoubleStud)

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.

RE: New patio roof beam

Quote (phamENG)

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?

RE: New patio roof beam

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 CDelta=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.

RE: New patio roof beam

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.

RE: New patio roof beam

Quote (Eng16080)

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?

RE: New patio roof beam

Quote (phamENG)

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.

RE: New patio roof beam

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.

RE: New patio roof beam

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.

RE: New patio roof beam

Quote (phamENG)

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".

RE: New patio roof beam

Quote (phamENG)

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.

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