My client has hired me a few times in the last few yrs. Lately, I cut down his closet doors in a basement room and added my typical hardware setup to good results. In todays bit, I installed shoji in a hall/entry closet.
The client wanted a “mill-core” type trim detail. This means NO trim and the dry-waller (or sheet-rocker) tapes the jamb directly to the drywall. This was popular with architects wanting a super clean line…NO CASING. Why I’m doing my blog on this job is to point out the custom made jambs on either side of the doors. A “Jamb” is the finish wood that covers the wall stud and drywall edges. 
A typical interior wall is 4-9/16″ thick. This incorporates a 3-1/2″ stud and a layer of drywall on either side of this stud. Using 4-9/16 or even 4-5/8″ wide material will cover the stud and drywall nicely. Any smaller and you have problems with gaps. In this case, we have NO casing. Here is how I made these…I ripped 3/4″ Birch plywood or Alder plywood to 4-9/16″ wide. I used my nice finish blade with 80 teeth for a smooth cut. I milled up 3/4″ x 1-1/2″ solid wood (to match) and glued and nailed these pieces to the edge I will use as the front or leading edge. On the back edge I used 1/4″ x 3/4″ and glued and nailed all pieces to be flush with the edge that goes against the drywall and stud. All sanded flush with 220 grt. The top part of this piece is notched to fit to the header and the valance box pieces (these are usually 3/4″ x 3-1/8″).
The 1-1/2″ pieces have the edges rounded over with a 1/8″ round-over bit in the router. If the closet has a light in it, use a valance piece on the front and the back of the track-box as the light will escape over the doors top and look bad. The bottom track will be trimmed to fit between the jambs. This can be used with casing. The main reason we did this was if the jamb is NOT installed plumb and very straight against the wall stud. The shoji will not fit nicely and have gaps. The light inside the closet will show in the gaps…looking like it was installed by an amateur.
The piece on the edge blocks that light some and looks much more elegant and finished.
