Plantation shutters, also known as interior shutters or colonial shutters, are a type of window covering consisting of solid panels or slats that are mounted inside a window frame. They are typically made of wood, but can also be constructed from other materials such as composite wood, vinyl, or PVC. Plantation shutters can help with insulation and energy efficiency. When closed, they create an additional layer of insulation, reducing heat loss in winter and heat gain in summer. This can contribute to better energy efficiency and potentially lower heating and cooling costs.