Window Treatments Don't Have to Be a Pane
Corner windows: If the windows meet at the corner with minimum space in-between, mount a track on the ceiling or just above the window frame and have the treatment draw back to the outside edges of the windows. Floor length or sill length is up to you. If you are mounting the track just above the window, you will want to cover it with a top treatment or make the track itself decorative. If ceiling-mounted, the track will become virtually invisible and you will not need additional treatment. If you prefer blinds, stick to vertical ones. Any horizontal blind or shade will snag at the corner where the windows meet.
Casement windows: If the windows are deep-set and open out, curtains can be mounted inside the frame. If floor-length or outside mount is preferable, a decorative rod or ceiling mount will work well. If the window opens into the room, you will need to mount the track outside and have the treatment clear the opening when drawn back so as to avoid catching on the open window. Blinds can be of the vertical or horizontal flavor if the window opens out. If it opens into the room, only the vertical blind will work. Here again, the treatment must be made wide enough to completely clear the opening.
Windows with sloping top: This is an architectural beauty. If possible, leave this window untreated. If sun and/or privacy prohibit leaving this window bare, draperies can be hung from the horizontal point down, thus leaving the sloped part untreated. Any type of blinds or shutter works well here.
Skylight: Though privacy is seldom the issue here, sunlight often is. Curtains can be fixed onto the window frame or mounted on a decorative pole and fastened to the ceiling around the window. Roller or vertical blinds can also be mounted; they come with special mechanisms that are mounted at reachable heights for opening and closing the treatment.
Horizontal windows: If these windows are off-center on the wall, you can create an illusion of symmetry by making one side of the window treatment extend farther beyond the edge of the window than the other. The draperies can meet in the middle of the wall instead of the center of the window. The illusion you've created will be that of a larger window that is centered on the wall.
Arched windows: As with the sloping top windows, these are best left untreated. If that is not possible, here again, treat the window from the horizontal point down. If you want to treat the arched part also, a semicircular shirred-on fabric can be custom-made to fit the arch. Wood shutters work beautifully on this type of window, and you can even cover the arch with wood slats, too.
Dormer window: These should be treated as casement windows. An interesting alternative would be to shirr fabric onto an oval or spring rod and attach to the beginning of the slope, away from the top of the window. Shirr the bottom onto another oval or spring rod and attach that end to the bottom of the window, thereby creating an angled window treatment.
Rosemary Sadez Friedmann, an interior designer in Naples, Fla., is author of Mystery of Color.