What is rabbet depth?
Simply put, rabbet depth is the depth of the recess at the back of the frame into which you load the contents of the frame.
Think about it this way: If the picture frame is a suitcase, the depth of the suitcase is the rabbet depth.
When the contents sink below the level of the back of the frame (when they drop entirely into the rabbet), it’s easy to hold the contents in the frame using a point driver. However, when the contents are thicker than the depth of the rabbet, they have to be held in place using offset clips.
Most commonly, rabbet depths range from ⅜” to ⅝” and are suitable for most art on paper with foam board backing, window mat board, and glass. However, depths of ⅞” to 1⅛” may be desirable for thicker stacks, and depths up to 2½” may be required for stretched canvas.
It’s important to remember that when it comes to floater frames, it’s a bit different. Since floater frames are front-loading frames, the rabbet depth is the depth of the recess at the front of the frame. For more on this subject, learn How to Measure for Floater Frames.