How to Measure Doors for Window Treatments Menu

Measuring sliding glass, patio, or French doors for window treatments is basically the same as measuring your windows. To start, grab a measuring tape, pen and paper. Or use the measuring worksheet on our web site.

Since the depth of most doors is too shallow for an inside mount, you’ll follow the same steps for measuring outside mount windows, starting with the width.

How to measure the width on french doors

Measuring Width

You’re going to take three measurements, one across the top, middle, and bottom of the door opening. Take the largest width and add at least 2 to 4 inches to it, to allow for maximum light coverage. Use this measurement for the width when ordering your door coverings.
How to measure the length on french doors

Measuring Height

Door heights are measured top to bottom, starting from where you’ll place the headrail, typically 2 to 3 inches above the door. Take your three measurements from the top of the frame to the bottom, on the left, middle and right, using the largest height for your order.
If you’re measuring sliding doors for vertical blinds, use the smallest height, not the largest, minus a half-inch, so they hang slightly above the floor.

Measuring French Door Windows

Window treatments for French doors are typically mounted directly on the door. When measuring, be sure to consider how they’ll fit around any hardware, such as handles, locks, hinges and hold down brackets.

How to measure the width on sliding glass door


Measure the width of the glass inside the door across the top, middle, and bottom. Take the largest width and add 2 to 3 inches to it.
How to measure the height on sliding glass door


Same for the height. Measure top to bottom on the left, middle and right, adding 2 to 3 inches above, and below, the top and bottom of the window pane.

Use the largest width and height for your order.

In most cases our factory makes no adjustments to outside mounted blinds, so they are sized to your exact measurements, plus or minus one-eighth of an inch. To ensure a perfect fit, please refer to the product specifications on our web site. If you have any questions about measuring your doors, don’t hesitate to call a member of our Customer Care team for assistance.

Now you’re ready to order! Go to, pick the style and color of the blinds or shades you want, give us your measurements, and your beautiful new door coverings will be shipped to you free of charge.

Here are some quick tips to remember:

  • Use a steel measuring tape
  • If you get a 1/16" or 1/32" increment for width, round down to the nearest 1/8"
  • If you get a 1/16" or 1/32" increment for height, round up to the nearest 1/8"

Always reference product specifications for complete measuring instructions.

Was this article helpful?