I would like to hear from manufacturers of frameless cabinetry on how you infill cabinets in alcoves and against walls. For instance, if an alcove measures 40" wide, do you build a 40" wide cabinet or do you build a 39" cabinet to allow for bowed walls, bad sheetrock joints, etc? If you build the cabinet smaller, how do you fill in the gap? Do you use a scribe piece on each side? How do you attach it and how do you scribe it? Do you make the filler flush with the cabinet front or with the doors?
We build AWI commercial millwork. We allow for a 1" filler on both sides of the cabinet. One filler is cut at 1" and attached to the cabinet in the shop at assembly with glue and staples. It is attached flush with the face of the cabinet. The other filler is cut at 3" and sent loose to the job site so the installer has plenty of material to work with if the walls are extremely bad. Once the cabinets are installed the installer can take a dimension at the top and bottom of the cabinet and cut the filler to match the wall. This filler is then attached with 1 1/4" chrome screws from inside the cabinet.
Comment from contributor B:
In a wall to wall application, allow for 1" on both sides for the filler. After building the box, screw a stick of 3/4" thick pine about 1 1/2" wide and about 1" less cabinet height to each side, with 1/8" sticking out past the cabinet face; so when installed the filler will be flush with the doors. Then when you set the cabinet you can scribe your filler to the wall, allowing 1/8" reveal between the filler and the door to match the 1/8" between doors. Once scribed, and you're happy with the fit, install with Liquid Nail. You can use wedges to hold it until the glue dries.