Miter and butt are examples of what?

• A. Casing joints
• B. Panel joints
• C. Dowel joints
• D. Frame joints

Answer: (A)

Joints used to assemble the trim around doors and windows are called casing joints. A miter joint is cut at a 45-degree angle on each piece so the two pieces meet cleanly at a 90-degree corner, giving a neat, finished look. A butt joint simply joins the ends of two casing pieces by butting them together, usually secured with nails and finished with caulk or a corner block for strength. These are classic casing joints because they’re specifically used to install the decorative trim around openings. They aren’t typical for panel joints (which join panels to rails/stiles), dowel joints (which use dowels for alignment), or generic frame joints used in structural framing.