A double skin facade is a high-tech facade system composed of two layers with a continuous space between them. The cavity between the two skins may be filled with naturally or mechanically ventilated air. Double skin facades are used as insulators to reduce energy use in a building.

This should not be confused with double glazing, where a narrow pocket of air separates multiple window panes within the same frame. Although the two features both achieve improved insulation, a double skin is a much more significant and exceptional feature and makes a greater difference in the architecture of the facade.

The continuous cavity separates two facade skins. A narrow sealed space within one double-glazed window does not establish a double-skin facade.