A fabric covered wooden valance, also called a cornice, is an easy do it yourself project. It requires very few tools and gives your windows a lot of decorator style appeal.
Step 1: Measure the Window
Measure the window where you will be installing the valance from side to side and add 4 inches. That will be the length of your valance. Decide how long you want the valance to be from top to bottom. You should then cut your plywood this length and width.
Step 2: Measuring and Cutting the Wood
The side pieces should extend 4 inches out from the wall. Cut the side pieces 3 3/4 inches long (They will butt up against the front piece to make them 4 inches long). So the two pieces, one for each end, should measure 4 inches by 3 3/4 inches. The length of the top piece of your valance should be the same as the front piece. The width should be 1/4-inch less than the 4 inches. This top board will be a nice shelf on top of your valance if you choose to use it in that manner.
Step 3: Constructing the Valance
Use glue to attach the top piece to the front. Use the finishing nails to nail the pieces together for a stronger bond. Attach side pieces to the front and top, again using glue and finishing nails. Make sure the nails are driven all the way into the wood for a smooth surface for your fabric. Allow the glue to dry completely before working with your fabric in the next steps.
Step 4: Measuring the Fabric
Measure your valance board from the back right, across the front to the back of the left piece. Add at least 4 inches to this measurement. Then measure the the width of the valance from across the top, over the front and then add 4 inches again.This measurement is the size you should cut your fabric and cotton interlining.
Step 5: Attaching Fabric to the Wood Frame
Use a hot iron to press all wrinkles out of your fabric. Lay the fabric, right side down, on a large surface or the floor. Place the cotton batting on top of the fabric. Then put your valance board on top. Start at the middle and working to the left, wrap the fabric around the board tightly and secure with tape to hold in place. Next work from the middle to the right, again smoothing as you go. Check the front of your valance to be sure the fabric is smooth before you start stapling in the next step. Use your staple gun to hold the fabric in place, stapling closely together, then remove all tape. You may trim any raw edges at this point.
Step 6: Hanging the Valance
To hang the valance, attach the L shaped brackets to your window frame two inches above the window and a third of the length of the window from each end. Be sure your drapery hardware is hidden by the valance. Sit the valance board on top of these brackets and screw the brackets into the underside of the top board of the valance.