DIY Crown Molding Valance

Measure for the overall width and depth of the valance. Prior to cutting, verify that both side returns match and are deep enough to accommodate other layers of window coverings beneath. If your are using two additional treatments, add at least 8-inches to the cornice returns to provide adequate clearance. Crown molding side returns give this valance depth and form and look best when extended at least 4 inches from the wall surface.

Use the miter saw and box to cut the two outside corners of the crown molding by laying a piece of premeasured wood at a resting angle against the back inside wall of the miter box and lining up the saw within the groves marked for a 45-degree angle cut. Use a gentle back-and-forth motion to cut the molding while holding it in position. Repeat the process for one end of each side return and verify proper alignment of angles. Use a hand coping saw to trim and define precise curves where they meet. Trim the two outside return ends with a 90-degree straight cut.

Use a damp cloth to remove any residue or particles from the mitered wood pieces. Lay the individual mitered molding pieces face down on the fabric, aligning pattern directions to match at both mitered corners. Verify the location of the mitered corners with patterns and designs to achieve the preferred visual placement.

Use the fabric spray adhesive following label directions to apply an even coat to the reverse side of the center piece of crown molding fabric, and adhere it to the front of the molding while ensuring you align any obvious pattern repeats at mitered edges. Fold all fabric edges neatly on the back of the molding. With your hand, smooth the fabric across the curves and bends of the molding while easing out any air bubbles or wrinkles, as needed Repeat the process for the two side-return moldings, confirming placement of any necessary pattern or design matches at the mitered edges.

Attach L-brackets on the inside returns of the crown molding, extending from the flattest portion of the inside edge and right angling them to be installed flush to the wall. Align the mitered corners to form the boxed frame and use the finishing nails and hammer on the inside section to join the mitered corners together. Use a tape measure and ladder to align and center the finished crown molding valance to the window. Use a cordless drill to mount the valance to the wall with the attached L-brackets.