Masonry Stem Walls - commercial construction

[Ben29]

The below detail is from IRC. I personally have never designed a masonry stem wall like this for a commercial building. Is this ever done?

I have a client that wants to install an 11'-5" tall wood stud wall on top of a 3'4" masonry stem wall. The roof truss bearing elevation is 14'-9". I'm not very comfortable with this idea. They want to do it to save money on masonry, but I feel that any rotation in the top of that masonry stem wall will cause issues for the wood framed wall and roof above.

 

[XR250]

Stop looking at the IRC and design from first priniciples.
I usually design the footing extra wide and add a bunch of rebar despite what the numbers say.

 

[Ben29]

Thanks XR. I just referenced the IRC because they had a handy detail which illustrated the concept of what I was talking about.

 

[phamENG]

That detail is all about lateral loads from a portal frame built per braced walls. It does absolutely nothing to counter the rotation your concerned with. That has to be handled separately.

In your case, you'll have a standard wood wall attached to the top of a cantilevered masonry wall. From top to bottom, you'll have pin, hinge, fixed. If you draw that free body diagram, you should see that it's stable. Now, design each component accordingly.