Vertical blinds are going to run from the top of your window down to the bottom of your window, or even to the floor. Vertical blinds can be installed on the inside of the window casing or on the exterior of the window casing, which would put the blinds on the top of the window but on the out edge of the wood.
Vertical blinds should be measured from where you want to install them If you are putting the blinds up on the interior of the casing, you will measure on the inside of the window. If you are putting the blinds up on the upper portion of the outside of the casing, you will need to measure from that point. For example, you have a 60" wide window that measures 40" long.
If you are putting the blinds up on the inside of the casing you most likely are going to need 58 or 59" across and 39" long, depending on the thickness of your casing and the trim on the window. If you are going to put the vertical blinds on the exterior of the casing above the window you are going to need to measure where you want the blinds to cover, and this is going to be about 62" or 64" wide, and will measure about 44" long. If you want to see the casing, you will need less, if you don't want to see the trim, and you don't want to see the casing you will need more.
The length of your blinds will vary. Some people like to cover only the window area of their window with the blind. This is fine if you are measuring the interior or the exterior situations of your window. If you are measuring to have the vertical blinds put on the inside of the casing it is difficult or impossible to have the vertical blinds that will be longer than the window because then the vertical blind will stick out on the bottom and look a bit funny after it is installed.
Think about what you want your vertical blinds to look like in the end. Now if you were to hang a string up there would it hang down nicely or is there something getting in the way? If there is something in the way of the string hanging down straight it is going to be in the way when you put the blinds up as well, so you don't want those blinds to be that long after all.
Measure where you want the blinds to be, and then draw this out on a piece of paper. After you draw it out on a piece of paper, does it look like what you thought it would? If yes, then you are ready to order, if not, you should re measure and think about where you want the vertical blinds to be placed.
