Lateral load path : Wood beam to wood shear wall

[CivilSigma]

Hi everyone,

I have a low beam/HDR that supports a partial height wall above, and I want to detail the transfer of lateral load from this beam into an adjacent shear wall.
Please see the attached detail.

Wall top plates are continuous, bottom plates discontinuous. So I need to transfer shear from the bottom plates into the adjacent shear wall.

I am using a strap to transfer the lateral load from the beam and into blocking attached the wall studs, shear wall sheathing is fastened to this blocking with boundary nails from the exterior.

Can I get a sanity check that this is a proper lateral load path?

 

[Aesur]

Assuming this is a block and strap shear wall, as long as the strap length is sufficient to transfer to the sheathing I don't see any major issue with it; otherwise maybe you need a longer strap or something tying the blocking together to transfer to the force to the sheathing based on sheathing capacity. I am curious why the 6x blocking, why not double 2x's flat or something like that.

If this is not block and strap, I'm not sure I follow where the force you are transferring is coming from because I would have expected the continuous top plate with proper splices to be your drag element.

Is your sketch to scale? That is a large trim stud compared to a small jamb stud, assuming no load transfer from above as well as there is no stud in line with the trim stud above the opening.

 

[lexpatrie]

Wall top plates are continuous, bottom plates discontinuous. So I need to transfer shear from the bottom plates into the adjacent shear wall.

I don't quite follow this comment, are you talking about the discontinuous bottom plate from the floor above?

 

[Eng16080]

I also don't fully understand your load path (as noted by lexpatrie), but in terms of dragging a lateral force from the header into the wall (or vice versa), the detail you show is typically my approach.

 

[EngDM]

There is a good document by woodworks about Force Transfer Around Openings (FTAO) however I'm not sure how you'd approach this if the opening is a door and the bottom plate is discontinuous.

 

[CivilSigma]

Thank you all.

So, what this detail shows is a transfer beam carrying a partial height wall above. The beam also supports some roof joists that bear on an exterior wall. So, my intent is to drag the lateral load from this beam (DL x CS) into an adjacent shear wall.

@Aesur: Yes, drawing is to scale. I'm showing a 6x6 post to support the beam, and a king stud adjacent to it.

@lexpatrie and @Eng16080: I am referring to the bottom plate of the wall the beam carries, which is discontinuous. The top plate is continuous to an adjacent shear wall. I am transfering shear forces in the bottom plate into the beam using SDS screws, and then from the beam and into the shear wall using straps.
My understanding is that the top and bottom plates will experience shear forces that need to be transfered and resisted by SW (or foundation) elements.

@EngDM: Thank you for the resource !

 

[KootK]

My gut feel on this is that there is no shear force in the bottom plate that needs to be transferred into the shear wall. Rather, all of the shear force resides in the top plates.

So, while the detail is well thought out, I'm not convinced there is a need for it in the first place.

I could be wrong but, based on what I've heard thus far, this is my read on the situation.