Board mounted valances should have the mounting board covered with either face fabric or lining fabric before attaching the valance to the board. In this video, watch a demonstration of how to wrap a mounting board in face fabric. The mounting board is wrapped like a gift, with the raw edges of the fabric at the top of the board, where the valance will cover the cut fabric edges. The corners are neatly folded, and any excess fabric is clipped away to reduce bulk. Once the board is neatly wrapped in fabric or lining, then the valance can be stapled to the top of the mounting board.

Cornice tops and legs are also wrapped in a similar way, with the cornice parts being wrapped in lining before they are assembled, in order to make a neat, professional cornice interior.