These basic tips will get you perfect measurements for window treatments!

  • Basic Measuring Tips

    1. Use a steel measuring tape.
    2. Measure to the nearest 1/8" of an inch, if the size is on a 1/16" mark, then round down to the next 1/8".
  • Ruler diagram to help measure for skylights.

Skylight windows are typically hard to reach and can be tricky to measure. Below is a helpful guide to getting perfect measurements for your skylight. knows that the perfect fit for a beautiful new window treatment all starts with an accurate measurement. If you’re planning a DIY window treatment project, our How to Measure for Skylights guide makes measuring easy!

You can also call our Customer Experience Center for an immediate quote once you have your measurements. Don’t forget you can always Find a Pro in your area to complete the project for you!

What You Will Need

Helpful Hints Before You Begin Measuring for Skylights:

  • For the most accurate measurements, only use a steel tape measure.
  • Don’t mix up width and height measurements. Always follow the width by height format (W x H) and mark them as such.
  • Measure to the nearest 1/8 inch. Never round up or down to the nearest half or whole inch.
  • If you’re measuring for more than one window, measure each one individually – never assume that your windows are the same size, even if they may look alike.
  • Side mount is not available for cellular skylights.
  • When assessing mounting depth, take into account any obstacles that may be in the window opening, such as window cranks or handles. These can prevent you from mounting a shade properly.
  • Side tracks must be mounted for both inside mount and outside mount, except in cases where the shade doesn’t come with side tracks.

How to Measure for Inside Mount Skylights

Follow the steps below:

  1. Check to see if your skylight has enough depth for mounting. Skylight window coverings typically need a minimum depth of 1 ½” to install brackets and mount the product.
  2. Width: Measure in 3 places: top, middle and bottom. Measure from edge to edge inside the window opening at the spots where you plan to place the mounting brackets.
  3. Height: Measure in 3 places: top, middle and bottom. If the window height is more than 96", measure the width every 48". Taller windows may need extra mounting hardware.
  4. Order your product at the narrowest width and the shortest height. Use the exact measurements, taking no deductions. The factory will apply the necessary deductions when making your product.

Other considerations for an inside mount skylight:

  • All corners of the window must be 90 degrees. If not, you will have to do an outside mount.
  • If the window is out of square by ¼” or more, you will have to do an outside mount. To find out if your window is out of square, take both diagonal measurements, from one corner to its opposite. If the difference between the two is ¼” or more, the window is considered out of square.

measure for inside mount

Featured Products