How To Measure Vertical Blinds

Because vertical blinds open and close like draperies, measuring requires a few special considerations. But before you get out your measuring tape (or yardstick), there are a few things you should know.

First, you will want to decide upfront if your vertical blinds will open one-way (like a sliding glass door) or two-way, with the vertical blinds splitting and half opening on each side (both right and left sides of the window or door).

Next, you will also need to consider where the door handle will be (if your new vertical blinds are for a sliding glass door). You may want to position the “stack” of the vertical blinds on the opposite side of the door’s handle for maximum convenience.

Additionally, you should know that most vertical blinds are mounted outside of the window frame because they usually require at least 4 ½" in window opening depth. As you may have guessed, patio door handles protrude and therefore will interfere with an inside mount. However, if you have sufficient window depth, they can be mounted inside the window frame. Now, on to measuring for your beautiful new vertical blinds.

For an inside or ceiling mount:
Depending on the size of the window or door, by mounting your vertical blinds on the inside, you will be partially covering the glass with the stacked blinds when they are opened (and to one side or both sides).

To measure for this:

1. Measure the exact width of the window opening across the top where the head-rail is to be installed.
2. Next, measure from the inside of the trim on the left side to the inside of the trim on the right side. Round the measurement down to the nearest 1/8". Note: The head-rail of all inside mount blinds will be made slightly smaller (1/16" to 3/8") than requested to allow room for mounting brackets and for operating clearance.
3. Measure the exact height of the window opening from the inside of the trim to the top of the windowsill or to the exact length that you want the blind. Measure the height in three places (the right side, the middle, and the left side of the window). Round the measurements down to the nearest 1/8" and use the shortest (smallest) measurement.

   Note: The blind will be made about ¼" to ½" shorter to allow for free movement of vanes at the sill or floor.
   

4. Measure the available depth of your window frame. Be careful not to include inside trim, window cranks or tracks. Measure only the space that is available to install the mounting brackets for the blinds.

For an outside or wall mount:
It is very important to understand that if you are measuring for an outside mount or a wall mount for your new vertical blinds, the blinds will be manufactured to the exact size that you specify.

1. Measure the width of the window opening (including trim). If there is room, add at least 4" to each side for overlap, to help ensure minimum light gap.
2. Measure the window opening height. Add at least 3" in height to allow for mounting brackets above the opening and add your desired overlap at the bottom. If your blinds will hang down to the floor or to the windowsill, deduct at least ½" for clearance.

Quick Tips:
Allow 3-5 inches above the doorframe to mount the vertical brackets.

When measuring the width for an outside mount, add a minimum of 3 to 4 inches on both sides of the window to prevent light gaps.

If your door handle protrudes it could interfere with the window treatment. If necessary you can order extension brackets. These brackets add depth to the head-rail, allowing the clearance for the obstructing door handle.

Need More Help?
Let us help you find a local installer who will handle the measuring and installing of your new vertical window blinds for you.