Exterior shutters have evolved into a standard feature on American homes. Functional shutters were initially designed for ventilation, light control, and to protect from wind and rain. With functional hardware, shutters rotate closed to block direct sunlight while simultaneously allowing for air to pass through the house. They could also be used as the first line of defense from precipitation and storms.
In the early American development all exterior shutters were constructed from wood. Wooden shutters were strong and maintained integrity when built from an exterior grade lumber (often Cedar or Cyprus). Today, various composites and metals are offered in addition to wood.
In years past, functional wood window coverings were far more practical than they are today. Modern conveniences make movable outdoor shutters unnecessary. Air conditioners allow homes to maintain consistent indoor temperatures when conditions rise above an acceptable level. Window screens used to protect homes from insects also prevent homeowners from operating exterior shutters when weather conditions are enjoyable.
Southern communities such as New Orleans or the Florida Keys regularly utilize functional outdoor shutters. Without much concern for bugs, residents often close louvered panels to allow cool moderate breezes to pass through the home. Common throughout these areas are multi-functional shutters that are constructed with movable louvers that rotate for adjustable light, ventilation, and privacy. Bermuda shutters, or bahama, shutters, are also popular for their awning-like functionality. Most all outdoor shutters are solid wood which offers moderate protection from high winds from seasonal hurricanes.
In most American regions functional shutters are primarily used to give an authentic historical appearance. Wood shutters mounted with solid metal hinges and shutter dogs present a distinct feel that non-functional vinyl shutters simply can not achieve. Towns or neighborhoods that strive to govern some level of historical accuracy regularly require the use of solid wood functional shutters. Louvered shutters are the most versatile functional panels. Raised panel or closed-weave board-and-batten shutters block all light and allow no ventilation, but may offer more protection.
Non-functional exterior shutters also have their place in American architecture. Stationary shutters are a practical, inexpensive alternative to functional shutters that add definition and character to a building. Often non-functional shutters are constructed in vinyl, plastic, pvc, or other composite material. Synthetic shutters are often easy to maintain, requiring an occasional washing. An open back results in a light shutter that installs quickly and does not trap water between the shutter and the building. Wood shutters can also be non-functioning, but need to be attached directly to a building with spacers to prevent trapped moisture and often require a strong anchor. Outdoor hardware can be installed to give the appearance of functional shutters. Non-functioning external shutters only need to vaguely appear operable, so size is not critical.
All styles are appropriate for non-moving shutters. Raised panels, louvers, or a combination of the two are the most universal and are applicable on most homes. Board-and-batten panels work best on more rustic or rough-sawn decors. Custom designs are offered by some companies for a unique one-of-a-kind application.