The "Standard-Size" Myth:
There is no standard-size window. Windows measurements vary in countless ways, and so do window treatments. It’s up to you to determine the best treatment option for your home.
Hardware can be mounted inside or outside the window frame to add the illusion of additional height and width. Hardware six inches or more above the window frame makes your ceiling feel higher. Stretching hardware six inches beyond the frame will make your window, and your room, appear wider.
How to measure:
Tools required for measurement include a pencil, a metal measuring tape (more accurate than fabric tapes) and a piece of paper.
Measure width in three different places:
at the top, the middle and the bottom of the window. For an inside mount, use the shortest width.
For an outside mount, consider how far you’d like the treatment to extend beyond the window frame on each side. The wider you go (as much as two to four times your window-width measurement), the fuller and more dramatic the treatment will look.
Remember - the lighter the fabric weight, the lighter the treatment will look.
More than decoration, window treatments have functional applications.
Light: with the right treatment you can enhance your home’s natural light, reduce glare, or block out light completely.
Privacy: window treatments will enhance your view out while preventing others from seeing in.
Insulation: lined panels and dense fabrics, such as velvet and linen, have an insulating effect to hold warm or cool air in the room.