How to build this sloped ceiling (see photo)

[Nate_M]

I'm looking for some suggestions on how to build the sloped ceiling underneath the stair platform. I can make a sloped ceiling plane, but then I don't' know how to build it out. All of the other methods I've seen require building a roof. However this does not have or need any roof framing. I guess I could build a polyline solid and save that as a soffit? Is that the best way to do it? It's kind of an odd setup if you ask me, but I need to include the detail in an as built plan for a remodel project.

 

Thanks in advance for any help you can offer.

[Chopsaw]

Ceiling planes come with framing options which I assume there is likely some framing in there to help support the landing.   By " build it out " are you referring to the triangle on the left side facing the camera ?   A custom 2 x 3 or 2 x 4 no room definition wall may work there or if not you can always fill it in with a polyline solid.

[robdyck]

3 hours ago, Nate_M said:

Thanks in advance for any help you can offer.

I would use a polyline solid. If framing needed to be shown in a plan set, I'd handle that using CAD in a section view.