My attic is partially finished and I plan to add a walk in closet in the unfinished portion. I'll be cutting out a section of drywall where the doorway to the closet will be. The closet will run down the middle of the attic, where the ceiling is highest. I'd like to avoid framing a ceiling for the closet, using the roof joists to attach the drywall so that I can retain all the ceiling height possible. My question is, for the side walls, can I run a bottom plate along the subfloor and then attach the studs to the ceiling joists rather than using a top plate? I'd then run 2x4's along the ceiling joists in line with the studs to create an A frame. I'm sorry if this is a confusing description, but if anyone follows me, please let me know if this will work.