Measuring for Curtains

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Curtains add style, privacy, light control, and insulation to your home. When purchasing ready-made curtains or placing a custom order, is it important to understand how to properly measure your windows. For the most part, window treatments are measured by their length and width, regardless of the style. Throughout our stores you will find curtains sized in this manner. 


Curtain Length

Before taking measurements, you must determine whether you will be installing outside or inside mounted curtains. Outside mounting places the curtains on the wall above the top of the window frame, while inside mounting places the curtains inside the window frame. This decision is a stylistic choice, and we are always happy to help you decide what would best suit your space. 

Outside Mounting 

Outside mounted curtains are most common, provide full coverage of the window, and create the illusion of larger windows. Within this style of mounting, there are a few length options. Depending on the look you are going for, your curtains can fall just above the window sill, below the window sill, or to the floor. 

  • Above sill: measure from about 0.5” above the window sill
  • Below sill: we recommend measuring at least 6 inches below the windowsill
  • Floor length: measure from the floor, or add a couple inches if you want the curtains to drape on the floor

At the top of the window, we recommend measuring to between 3-6” above the window frame. For outside mounting you must also consider the length of the curtain rod. We recommend selecting a curtain rod length that extends beyond the window frame by 3” on either side. To find this measurement, simply measure the width of the window from one edge of the window frame to the other and add 6” inches.

Inside Mounting

Inside mounted curtains give your window treatments a modern look. This look is usually achieved by using utility or spring tension rods. Curtains can be inside mounted at the top or  middle of the window. Hanging curtains from the middle provides privacy while letting in unfiltered light from the top portion of the window. Take your measurement from the desired mounting point to the window sill to get the appropriate curtain length. 

Curtain Width (Fullness)

The width of a curtain is more commonly discussed as fullness, a measurement that considers how much extra fabric will hang across the window. Fuller curtains have a richer look and provide more light and privacy control. Fullness is determined by multiplying the width of the window by the recommended fullness of a given style of curtain. Below is a list of styles and their recommended fullness

  • Grommet style: 1.5-2 times width
  • Curtains shirred/gathered onto rod pockets: 2-3 time width
  • Tab style: 1.5-2 times width
  • Sheer and lace: 3 times width (some prefer less fullness so the pattern of the lace can be seen better)

Helpful Tips

  • Curtains hanging from ceiling to floor make the room appear larger
  • In a room with windows of various sizes, using curtains of the same size will make the room feel bigger
  • Select curtains that are lined, or shop our selection of liners, to improve energy efficiency in both the summer and winter.