How to Measure WindowsExpress Blinds, Draperies, and Shutters | Express Blinds & More
How to measure a window

Are you replacing bathroom windows, adding shutters to your kitchen, or upgrading your storm windows? If so, you will need to know how to precisely measure a window in order to ensure no surprises on installation day.

Taking Measurements

When measuring a window there are three measurements that must be taken to insure the correct size windows are ordered.

Measuring Width:

  • When measuring the width, you must measure between the jambs at three different points: top, middle, and  bottom of the window opening.
  • You must also measure the surface of the jamb (do not measure the trim strips or parting beads).
  • The smallest of these measurements will be the one you give to the manufacture.

Measuring Height:

Measuring for height is a little different than width.

  • You will first measure from the high point of your window measurement tipswindowsill to the top of the window opening.
  • You then must make three measurements as before: the left side, the center, and the right side of the window.
  • Again the smallest measurement will be the one you use to order the window.

Measuring Depth:

  • Make sure there is at least 3 1/4 inches of opening depth between the inside window trim and the outside blind stop strip.



Measuring Tips

Whether you are replacing bathroom windows, or adding flare to your home with new shutters, knowing how to give the correct window measurements is important. Here are some extra tips to make sure you are never wrong!

  1. When ordering your windows, only provide the opening size. The manufacturer will deduct everything else. [Source]
  2. In order to check if an opening is square, measure diagonally from each top corner to the opposite corner on the bottom. If these two measurements are not the same, then the opening is racked, which is something you should share with the window or shutter maker. [Source]
  3. There is no need to measure pulleys and parting strips when measuring for depth, since they will be removed when the window is installed.

Helpful Terms

  • Jamb: “A window jamb is part of the structural support of a window. Jambs are located inside the framing of the window, along the top and sides, and in the case of windows which open, jambs can house tracks or rails used to manipulate the window, along with devices such as latches which are used to lock the window when it is closed.” []
  • Blind Stop: A rectangular molding seen in a window frame. It is nailed between the outside trim and the outside sashes. It helps stop intrusions among other things. [Source]

Knowing how to measure a window is a great skill to have, and it is very beneficial when it comes to home improvement, home design, or home repair. The next time you are trying to measure windows in your home or office and find yourself in a “jamb”, remember these helpful hints and the measuring process will be a smooth process.