Choose puddle-length draperies for a formal or historical look for your room. Standard puddle draperies extend anywhere from 4 to 8 inches beyond the floor for a "puddle" of fabric on the floor. Choose puddle-length draperies for curtains that remain fixed and are not in high-traffic areas.
Trouser-length draperies blend the drama of puddle-length draperies with the more practical floor length by extending curtain fabric just 1 to 2 inches past the floor.
Standard floor-length draperies, also called full-length draperies, should just touch the floor or hang only 1/4 to 1/2 inch above the floor. Floor-length draperies are a popular choice for many decor styles.
Sill-length draperies at the standard length end right at the window sill for a less formal look or to accommodate items below the window, such as radiators or furniture. Sill-length draperies are also a common choice for children's rooms for safety reasons.