Freestanding Wood-Frame Wall

[Apache1]

Hello fellow engineers, this residence I'm working on has an open patio with jacuzzi where they want to have an exterior partition wall (wood framing) to make the jacuzzi area private. This wall is freestanding as it won't be braced at the top by any roof framing. Further, they want the door in this wall to be full height, so no framing can run over the top of the door opening.

My thought right now is to run a wood beam from the corner of the house over to an HSS square tube that is set next to the door opening. I would do this on each side of the door. The lateral load from wind and people pushing on the wall would go into studs that are framed up to the bottom of the beam. I'd provide attachment from the studs to the sill plate at the bottom, and from the studs to the beam at the top to transfer the lateral load into the foundation wall and beam, respectively. The beam would then transfer the lateral load into the wall corner on one end, and the HSS tube on the other end. This HSS tube would effectively be a cantilever steel column with a moment connection at the bottom, so that may be difficult to do on a 8" thick foundation wall.

Should I tell them this wall needs to be concrete and design it as a retaining wall?

Do you see a better or easier way to build this wall if it's framed? Thanks!

 

[XR250]

What you are proposing sounds reasonable if you can get a decent connection to the foundation wall.
Certainly begs to be concrete though.

 

[Apache1]

Yeah...and one thing I was thinking about is since, unlike a concrete wall that retains soil, the lateral load on this wall could come from either direction. So I was wondering where I would put the rebar in the wall, and if the wall should be thicker so I can put rebar in both faces.

 

[StrEng007]

Two things:
The door you're looking to install will act more like a gate. Most architectural doors will require a top frame and a surface to mount into.

You could save the need for formwork by using 8" CMU. It doesn't sound like you have a very tall wall and with low wind speeds, you could use (1) bar (per your design) at the center of each filled cell (spaced per your design).

 

[Apache1]

Thanks for your input. I told the owners that I think the wall should be CMU and they're not happy. Apparently some other houses in the neighborhood have walls just like this one and they were built with 2x stud framing and a standard strip footing below. They can't understand why the wall needs to be 8" CMU with a 36" wide footing. I've been getting into situations like this quite a bit recently. For the life of me I can't figure out how this wall would be ok as a standard 2x framed wall...

 

[EcoGen]

As an alternative (and to avoid using structural steel or concrete) you might want to consider using base moment connections with 4x4 posts spaced on center instead of 2x4s. You can connect the base to the concrete using a moment connection (see Simpson catalogue) then you can determine the post spacing based on the maximum moment capacity of the post base moment reaction. So maybe you can get more than 24 inches on center for the posts but then you'll still have to look at the sheathing and or your horizontal blocking and see how far they can span. That way your wall will still be about 4 inches thick. Not sure how much actual capacity you can get out of your post moment bases though.

 

[Enable]

I told the owners that I think the wall should be CMU and they're not happy. Apparently some other houses in the neighborhood have walls just like this one and they were built with 2x stud framing and a standard strip footing below. They can't understand why the wall needs to be 8" CMU with a 36" wide footing. I've been getting into situations like this quite a bit recently. For the life of me I can't figure out how this wall would be ok as a standard 2x framed wall...

Next time an owner says something like that respond with: "That's fantastic! So we have a real-world load testing proving the concept that otherwise fails design checks. That sometimes happens. All I need to know now when is the last time a 1/50 year wind storm came through here. Can you confirm the exact date and wind speeds? Then we'll be all set to build it that way"

When crickets ensue you say well...CMU passes the design checks so, I guess CMU then?

I was going to suggest the bases EcoGen_Consultants mentioned. Simpson makes some moment saddles that might work. However, I would be very careful with the posts adjacent to the door. If this is a high-end residence they wont take too kindly to those posts deflecting and binding the door. I would think a 6x6 at the minimum would be what you're looking at to make it work but of course run some calcs.