Curtains add color, pattern and texture to a room, as well as providing privacy. As you like your front door window curtains, you add energy efficiency and insulation to their benefits. In addition, lining your curtains helps reduce noise, protect against bleaching, block light, and will make the curtains hang better. For a little more money and time, you can extend the life of your curtains and possibly save on heating and cooling costs.
Measure the width of your windows from the outer edges of the windowsills. Multiply this number by three to create the amount of width you want for complete, but simple, window curtains. For this example, the window is 40 inches wide. Multiply 40 inches by three and you have 120 inches. Next, share this with the width of your chosen fabric. If the fabric is 45 inches wide, divide 120 by 45 and you have 2.6. Round up to the nearest integer, or 3. This is the number of weave widths.
Measure the length of your window to determine how long you want your curtains to be. Front door curtains generally fall to the windowsill, just below it or in the floor. Add 2 inches for hem and seam allowance. Say your desired length is 58; length is 60 inches. Multiply your length, 60 inches by three, the number of fabric widths, and you have 180 inches. Now divide this by 36, the number of inches in a yard, and you find that you need to buy five feet of fabric for curtains and 5 feet of fabric for the liner. This is enough to make two curtains for a window.