How to Make Lined Curtains With an Inverted Box Pleat

Measure the width of the area to cover and divide this in half. This will be the finished width of each side of drapery.

Multiply the finished width by the desired fullness. Maximum fullness is three times; minimum should not be less than one and one-half times. To this measurement add 6 inches for side hems. This is the cut width of the fabric required per side.

Add 12 inches to the desired finished length. This is the cut length of the fabric required.

Cut the fabric to the cut width and cut length required. Sew sections of fabric together, if necessary.

Cut the lining length equal to the finished length, plus 9 inches. Join widths of lining together, as necessary.

Turn the bottom hem of the fabric up 4 inches twice and sew in place. Turn the side hems under 1 1/2 inches twice and press. Turn the top over 4 inches and press.

Turn the bottom hem of the lining up 3 inches twice and stitch in place. Turn the top down 4 inches and press.

Position the lining on the fabric, wrong sides together. Tuck the side edges of the lining under the pressed side hems of the fabric, the top edge of the lining sits 1/4 inch down from the top of the fabric. Pin the fabric and lining together along the top. Turn the side edges of the fabric over on the pressed creases, encasing the lining, and sew on the inside pressed edge.

Measure the flat width of the panel. Subtract the required finished width, (which is the fabric required for spaces), from this measurement. The result is the amount of fabric available for pleats. Calculate a number that will divide evenly into both the fabric required for spaces and fabric available for pleats. For example, if the finished width required is 20 inches and the flat width is 60 inches, there are 20 inches for spaces and 40 inches for pleats. Five will divide evenly into both figures; there will be 5 spaces of 4 inches and 5 pleats of 8 inches.

Mark the spaces and pleats along the top of the panel, starting with a space. For example, the first end of space will be marked at 4 inches, the next mark will be the end of the first pleat, at 12 inches. Next is a space of 4 inches, ending at 16 inches, then a pleat of 8 inches ending at 24 inches.

Align the pleat marks, right sides together, and sew, perpendicular to the top edge, toward the bottom hem, 5 inches.

Finger-press the center crease of each pleat. Press this crease toward the back of the heading, forcing the pleat to form, equal amounts to the right and left of the creased center. Press the pleats flat and stitch in place across the top edge of the panel