How to calculate how much fabric is required for curtains

To calculate how much fabric is required for curtains, you must first determine the length, then the width of the area you wish to cover. These calculations will help you when making your own drapes. Near the bottom of this article, you will find how to calculate ready-made drapes.

Length:

Measure the height of the window from the curtain rod to the floor or the level you wish the curtains to reach. Add approximately 10 in/25 cm for finishing both the top and bottom hems.

Width:

For gathered curtains, measure the width of your window and multiply by two. Add 2 inches for each side hem of each curtain, whether you are going to have one, two or more curtains. Most fabrics come in a standard width of 45 inches /1.2m, so you may need two lengths of fabric to make one curtain.  Divide the total width by the standard width by the standard width to see how many lengths you will require.

Standard curtains and drapes come in standard sizes. Ready-made drapes are usually less expensive than custom curtains. The standard length in a ready-made curtain is 84 inches in length. For shorter windows, sixty-three inches is the standard length, and 95 inch lengths are sometimes used for larger, high windows. For the width, simply double your width in curtain fabric.

Curtains that hit the floor with a one inch break are called puddlings. If you do choose to puddle your curtains, make sure you go all the way with at least a foot of extra fabric. Do not assume that you have to use exactly the same window treatment on every window in a room.  If you use different types of treatments in one room, definitely use the same fabric for continuity. 

To compensate for a room with little architectural interest, try using curtains with contrasting borders, tassels, appliques, or beads.  In a modern house, keep it simple with scrims or shades that do not compete with the room's clean lines.  If your ceilings are low, hang your curtain rod higher than the window frame. This will make the panels longer and your room will feel bigger. 

Most fabrics lend themselves to being used as draperies, unless they are extremely stiff or heavy. Textiles woven with materials such as hemp or sisal do not drape well; use them as window shades instead. Even corduroy can make great looking curtains.  Use linings to prolong the life of your curtains. They act as a sunblock preventing any fabric, but especially costly ones, from fading prematurely. Linings are a must with statelier fabrics, or when privacy is necessary. When curtains are pulled back the linings show, so use a sateen fabric.  Simple curtains are best made from gingham or batiste. You will get an airy and open feeling, but just be prepared to replace the curtains sooner.  Help insulate your rooms by using an interlining of cotton or wool flannel. The added weight will not only keep the cold out, but will also give the draperies a grander appearance.  If you choose a big bold stripe for a window curtain, keep the style a little conservative so it does not become overwhelming.  Never use a valance on french doors, because it will get in the way of the doors. Be careful when covering your shades with plaid. Unless the grid is completely square, it can make your shades look off measured. If you are blessed with a great view keep your window dressing to a bare minimum.