Measuring windows for drapes is a good idea before spending money on dressing a window. It's not that difficult to do, and it means saving time and energy in the long run. The first step is to decide how tall you want the drapes. The next step is to decide how the drapes will function. Once this is determined, measuring only requires a few simple calculations.
Decide how high to set the drapery rod. The general measurement is 4 to 6 inches above the top of the window. However, if you have low ceilings, you may want to hang the rod against the crown molding of the ceiling. This is a good idea for ceilings that are eight feet tall. Attaching the rod against the ceiling will add height to the room.
Decide on the type of drapes. For rod pocket drapes, measure from the top of the pole to the floor or where you want the drapes to stop. Add 1 inch for small rods and 2 inches for larger rods. For panels hung from rings, measure from the bottom of the ring to the floor or where you want the drapes to stop. For tab top drapes, measure from the bottom of the rod to the floor or where you want the drapes to stop. Add 1 to 2 inches for the tabs. For grommet tops, measure from the top of the rod to the floor or where you want the drapes to stop. Add 1 inch for the grommet allowance.
Decide how the drapes will function. If the drapes will open and close, you need the measurement of the drapery pole, not including the finials. If you want the panels to hang with some fullness, each panel needs to be 1 1/2 to 2 times the width of the window.
Purchase the drapes. If you are ordering your drapes, you need to write the width measurement first and the height measurement second. An example of a drapery measurement would be 102 by 84 inches. The width is 102 inches and the length is 84 inches. If you are purchasing drapes, look at the packaging carefully. Some manufacturers package panels individually while others package two panels together.