Corner Close Up Published December 13, 2010 at 1952 × 2592 in Traditional Repair of the Abyssinian Meetinghouse ← Previous Next → Corner Close Up The interior joint of the jamb and sill. The top sash will be held in by the exterior casing (a divergence from traditional Plank Frames) and the vertical dado will hold the parting bead, which separates the top and bottom sash.