For cathedral ceilings leave approximately four to six inches above the window trim as a guideline.
Height to put curtain rod.
Go high a rule of thumb from architectural digest is that curtains should be hung between 4 to 6 inches above the window frame so install your curtain rod accordingly.
Assuming you re outfitting a living room or bedroom with average ceiling height 8 feet high an interior designer s rule of thumb would be to mount the curtain rod about a half foot above the top.
When you hang the curtain rod high it will make the window appear taller.
Make a mark about four inches above your window for mounting hardware.
This is a traditional height though you can cheat an inch or so either way depending on the height of your ceiling and the length of your finished curtains.
Hanging curtain rods high above the window frame adds height to the wall and works best with long panels or drapes.
For grommet curtains you will need to take into account the placement of the grommet.