Door casing is set back off the face of the jamb approximately 3/16 inch

• A. 1/8 inch
• B. 1/4 inch
• C. 3/8 inch
• D. 3/16 inch

Answer: (D)

When you install door casing, you set it back from the face of the jamb to create a small reveal that accounts for wall finish and keeps the trim from rubbing as the door moves. A setback of three-sixteenths of an inch is a common practice because it provides enough clearance for drywall or plaster thickness and any finish, while still letting the casing present a clean, balanced frame around the door. If the setback is too small, the casing can press against the jamb or door as finishes settle or when the door swings. If it’s too large, the gap becomes obvious and the trim looks misaligned with other pieces. So three-sixteenths of an inch is the typical, appropriate amount.