How is a panel wall different from a curtain wall?

In modern building construction, both panel walls and curtain walls are nonbearing exterior walls, meaning they do not support the structural weight of the building. However, they differ significantly in their design and assembly:123

• Curtain Walls: The most common type is supported by a metal gridwork (typically aluminum) consisting of vertical mullions and horizontal muntins attached to the building frame. The spaces within this grid are filled with various transparent or opaque panels.4
• Panel Walls: This type of curtain wall lacks a gridwork of mullions and muntins. Instead, it is constructed from large, prefabricated rigid panels—often made of precast concrete, aluminum, or steel—that connect directly to the building floors and span the distance between them. Transparent openings in these walls are created by cutting holes directly into the panels.4

Both systems serve to resist wind forces and provide weatherproofing for buildings with skeleton structures.43