The definition of a facade is the front of a building facing a public space or an artificial front or appearance by someone. An example of a facade is the front of the local mall.

A wide variety of facade systems may be used in modern multi-story buildings, which are:

• - Brickwork and stonework (masonry)
• - Curtain walling.
• - Precast concrete panels with various types of finishes.
• - Insulated render.
• - Metallic cladding.
• - Tiles and stone veneer panels

The building façade provides the separation between the inside and the outside environments but is also required to provide acceptable light levels and a visual connection with the outside in the form of views out of the building. The façade may also be required to provide the building user with openable windows for ventilation.

The separating functions include:

• - Weather tightness including the elimination of water ingress and control of air permeability and resistance to wind actions;
• - Insulation (both thermal and acoustic);
• - Control of solar gain and ultraviolet radiation and the management of views into the building.

The building façade also provides the owner and the architect with a canvas on which to create an image representing the owner’s business, ideals or outlook.

By means of the solar and thermal protection it creates, it saves a great deal of air conditioning costs in the summer, as well as protects against the sunburn effect and greenhouse effect especially in glass curtain façade or skylight applications.