They usually do not. The proper position is ½ inch above the floor for free hanging curtains. This distance allows for mopping and cleaning while creating the illusion that the curtain touches the floor.
Standard curtains typically hang from about a half-inch from the floor to halfway between the window trim and average-height ceiling. But to maximize visual height, let the walls determine your curtain's length; in a living room, library, den or bedroom, the longer the panels, the better.
The answer to this question is important because it can affect the way we do our decorations. Yes, curtains should be long enough to touch the floor. With a few exceptions, the longer the curtains are the more stylish and elegant it will look. This is why most standard ready-made curtains are lengthy.
1/2" above the floor. Polished and stylish. This is my favorite length, and it's popular right now for good reason. Floor-length curtains will elongate your window and make your room feel taller.
A common rule for displaying curtains properly says the curtains finished width should be at least 2 times the width of your window (if not more - sheers can be 3 times the window width) to achieve a look of proper fullness.
Standard curtains come in three lengths—84 inches, 96 inches, or 108 inches. "Generally, you want to stay away from the 84 inch standard curtains unless you have very low ceilings.
The material should barely touch the floor or hover half an inch above. Use this approach for café curtains, too, short panels covering only the lower portion of a window, hitting the sill, which works well in kitchens and bathrooms, where long drapes or curtains aren't practical.
Hovering an inch or less above the floor
This option is also more forgiving than those that precisely hit the floor, which means your measuring and hemming won't be derailed if it's a few millimeters off. It also means you don't have to worry if you have slightly uneven floors.
Interior designers note the bottom of your curtains should fall to the floor, and you can even let them “puddle” a bit. However, if you don't want your curtains to drag on the floor when you open and close them, let them stop about an inch from the floor, but no more.
When hanging curtains, it is important that the curtains are the right length. Curtains that are too short make the room look short, stubby and awkward. The cut the length of the wall, making both the window and the room look smaller. An example of curtains that are way too short!
When you buy them in stores or online, there are two standard lengths: 84 inches and 95 or 96 inches. The length of the curtain dictates the height of the rod. If you buy 84-inch-long curtains, the rod must be mounted roughly 84 inches from the floor if the curtains hang from the rod without rings.
If you are interested in stationary panels, you will want your curtains to be long enough to lightly brush the floor, but not so long that they bunch up in a pile. A good rule of thumb is for your curtains to break anywhere from a ¼” to ½” from the floor, similar to a break in pant legs on your shoe.
As a general rule of thumb, curtain width should be two to two-and-a-half times the width of the window. Curtains are typically sold as pairs, but you may need to double up depending on the size of your window.
To get the measurements, measure the width of the rod from left to right. For instance, if your window measures 72” wide, you will need curtains that will give a maximum width of 144” (window width x 2 = 144”.)
Making Your Room Look Larger or Smaller with Curtains
High-hanging curtains with long vertical stripes create the illusion of height, which is excellent for low ceilings. However, short curtains and horizontal stripes shorten your wall height and make the room appear smaller.
When measuring for curtains, keep in mind that curtains usually come in only a few different lengths: 63 inches, 84 inches, 95 inches, 108 inches, and 120 inches.
As a general rule, drapes will be open during the day, so make sure the curtain rod extends at least four inches on each side of the window's inside frame. To create the illusion of a wider window, extend the rod up to 10 inches beyond the window's frame.
The top of most of our windows are 8ft, and we used 108″ panels almost everywhere. So we hung our curtain rod about 13 inches above the windows. The higher the curtain rod, the taller your window will appear. I recommend to always install a rod closer to the ceiling than the top of the window.
Just Hitting the Floor or Sill
The fabric should just touch the floor or hover 1/2 inch above. This is also a great approach for café curtains (short panels that cover only the lower portion of a window and hit the sill), which work well in spots like the kitchen and bathroom, where long drapes aren't practical.
Hanging long drapes on a short window is one of the easiest ways to increase the importance of the window and bring it into proportion to the room. Short drapes on a short window call attention to the size of the window and reduce the significance of the room, window and drapery style.
If you want a little bit more length out of your panel, ring clips are a great way to add 1-2 inches, since the clips means the fabric hangs just below the drapery rod.
In this case if you hang a curtain too high it could look a little off, especially if there is a lot of bright light coming through showing where the actual window is. In that case you should hang them about 8 inches or less above the window frame.