Box pleats, or pleats of any type or kind, are used in both tailored clothing and in upholstered items. They are generally employed for the purpose of reducing the width of a broad piece of fabric and bringing a fuller look. They also are used to create a more dramatic or stylized appearance. Considered a double pleat, a box pleat is a back-to-back knife pleat, which springs outward instead of falling flat as the knife pleat does.
As a part of the design of a garment, box pleats are used in a variety of ways. Commonly they will be seen on skirts, creating a fuller look while giving the wearer an appearance of a more narrow or smaller waistline. As opposed to the narrow tailored skirt, a skirt with box pleats allows for more freedom of movement.
Box pleats are also often seen as part of the design of shirts and blouses. The most usual place for pleats to appear on a shirt or blouse is in the center of back, allowing for more reach and at the bottom of the sleeve at the point where the cuff is joined to the sleeve. Pleats are a common addition to many garments and add both comfort and style.
In a box pleat, the two upper folds of the pleat face in opposite directions, while the two under folds are laid toward each other. The seam is located on the inside of this type of pleat. Box pleats are created in a 3:1 ratio. This means that for every 3 inches (7.62 cm) of fabric, a 1 inch (2.54 cm) pleat is made. Considered to be the most basic type of pleat — and the basic beginning form of the box pleat — knife pleats also use the 3:1 ratio; however, unlike the box pleat, they create a flat appearance while still employing the same amount of fabric.
An inverted box pleat has the seam located on the outer or visible side of the piece, creating a more dramatic look. The inverted box pleat is commonly used on jackets and outerwear. On this type of garment, the pleat is not only used to create a more fashionable look, but it is also used to afford the wearer more comfort and less restricted movement.
Double box pleats, also referred to as stacked box pleats, use a 5:1 ratio, which means that for every 5 inches (12.7 cm) of fabric, 1 pleated inch (2.54 cm) will be created. The result is a more supple, deeper pleat. Designers and dressmakers tend to use this type of pleat when more fullness in a garment is desired.