Measure for Vertical Blinds - Vertical Window Blinds

Why do I need to add 3 inches to my vertical blinds?

For inside mount vertical blinds you will not add to the height but enter the exact window size. With outside mount vertical blinds you will need to add about 3 inches to the height so the headrail can be mounted above the window frame and the vertical vanes will extend past the bottom of the window for proper coverage.

Most windows are not deep enough for inside mount vertical blinds. In order to mount vertical blinds inside the window there needs to be 3 1/2 inches for the entire blind to fit within the window frame. With windows such as patio doors, this depth is reduced due to handles on the sliding door.

Regardless of whether you are choosing a vertical blind or a horizontal blind, when mounting window blinds outside the window frame, the blinds need to be larger so they extend past the edge of the window for proper coverage. For complete instruction for measuring window blinds visit our measuring instructions.