A curtain wall system is an outer covering of a building in which the outer walls are non-structural, utilized to keep the weather out and the occupants in. Since the curtain wall is non-structural, it can be made of lightweight materials, thereby reducing construction costs. When glass is used as the curtain wall, an advantage is that natural light can penetrate deeper within the building.
The curtain wall façade does not carry any structural load from the building other than its own dead load weight.