While French doors can be functional, they are typically used more for aesthetic purposes, to create a dramatic effect. For example, a great use of this style element is to make indoor and outdoor living spaces feel connected. A French door-style opening from the kitchen onto the patio area ties the two spaces together. A pair of French doors opening onto the balcony from the master bedroom brings the outdoors inside.Because a French door is so versatile, it may be a repeating theme in a home. A pair, or in some cases, many pairs of doors are often used to keep an open feel. A French door, or many doors, are sometimes used in a stationary position and locked into place with a bolt or post. Such a formation is used in place of a solid wall, to keep the space light and airy and to create interest.