How to Calculate How Much Pleating Tape for Pleated Drapes

Mount the chosen curtain rod in position on the window.

Measure the length of the curtain rod. Add twice the “return” measurement, which is the distance from the wall to the front of the rod. Add 8 inches for a 4-inch overlap in the center. This is the finished width of the curtain.

Determine the desired fullness of the drapes. Typical drapes, with a regular lining, are two and a half times fullness. Sheer drapes are three times fullness, and heavier drapes, or drapes with blackout lining, are two times fullness.

Multiply the finished width by the desired fullness. Add 12 inches to accommodate four 3-inch edge hem allowances. This is the total width of fabric required. For example, a window that is 100 inches wide, with a return of 5 inches, at two and a half times fullness, plus overlap and edge hems, requires a panel of fabric 280 inches wide: 100 x 2.5 + 10 + 8 + 12 = 280. For center split drapes, divide this panel in two.

Purchase the same amount of pleating tape as the total width of fabric required.

Attach the pleating tape to the drape. Position the tape so the first channel is 4 inches from the center edge. This allows for the 4-inch overlap. Place the last channel 5 inches from the outside edge, which is the start of the return. Attach the tape in the chosen method and insert the four-prong pins, according to the manufacturer's directions. For two times fullness, skip four pin channels between pleats. For two and a half times fullness, skip three channels; for triple fullness, skip two channels.