Bolting into narrow face of multi-ply stud packs

[txeng91]

One of the details in the IRC specifies that shelf angles for masonry veneer be atteched into 2-2x studs with 7/16” lag bolts. My intuition is telling me that this detail sucks since it seems that if the lag bolts coincide with joints in the plies it’s bad news. Usually for shelf angles I will through bolt the angle to 2-2x blocking between studs, while anchoring the blocking to adjacent studs with clip angles sized for shear and eccentricity

I am currently working on a reidential project where I would like to attach steel channels to the face of built up 2x stud columns using a clip angle or end plate with lag screws into the face of the column. I am using the steel channels as rim boards on some shed type porch roofs with rather impressive cantilevers (7’-10’ from beam line in addition to 3’ corner cantilevers) where running drop beams with rafters going over the top is not an option an minimizing depth (12” or less) is a must. My goal is to mitigate cost while also reducing deflections of the roof corners. I am able to get a wood only design to work within code deflections but I don’t feel great about nodal deflections at the corners (~1/2”-3/4” at dead load only) and it would require a ton of lvl memvers especially near the corners, which is why I am exploring the steel channel option, also there will already be a considerable amount of steel framing in the rest of the structure due to other conditions.

The reactions at these channels would be be pretty light, maybe 3 kips max. I have not been able to find anything on bolting into the narrow face of muitiply membets or if having bolts located at joints in the plies is a concern. I see my options as providing steel columns where the channels attached into the wall, which will increase cost, or providing built up stud columns and bolting the channels to that. Maybe I provide periodic [pre][/pre]bolts in the stud columns through the wide face of the stud to prevent splitting of the plies. The middle ground would be to use solid engineered wood columns. To simplify this overly long post is my concern about bolting into the narrow face of built up stud packs legit or am I just being overly cautious?

Thanks in advance for any input.

 

[XR250]

I am not a big fan of it except for very light loads. Can you let the channel into the studs to take the vertical loads and then fasten the web to the narrow face with some Simpson SDS screws to give it stability?

 

[KootK]

I think your concern is legit. Solid wood post for me. once it's behind sheathing, you don't exert great control over the location of the fasteners. I don't know that fasteners have been tested in anything similar to a ply joint and I can imagine significant differences in behaviour.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[DBronson]

dnlv:

Sorry, don't know of any information on edge bolted wood connections. My guess is it might violate NDS minimum edge distances.

However, you might consider simply asking the framers to rotate those columns 90 deg - make the face of the 2x's parallel to the wall line. They would have to pack out the column with ply to make thickness, but that's pretty routine. Also, you might look at using shear plates for your connection. A single 4" plate on a 3/4" bolt looks like it's good for 3,500 lbs. The carpenters would only have to drill a single hole plus the dap for the plate.

Of course, the effects of an eccentric 3k load would have to be dealt with.

Regards,

DB

 

[txeng91]

Thanks for the replies. I like the idea of providing a bearing and shear connection for redundancy, for some reason my mind was stuck on using a clip angle with lag screws. If you wanted to conform to NDS edge distances you could use a 1/2” or 3/8” lag centered on the narrow face of the stud but that would be difficult to align in the field, especially if is through the sheathing. I’ve always stayed away from attaching into the narrow face of multi-ply columns but wanted everyone else’s opinion since it is called for in the code. But of course there are many wood framing details and provisions in the IRC/IBC that can be picked apart.