What is a Curtainwall Glass System?

A curtainwall is defined as thin, metal-framed containing panels of glass. This framing is attached to the building structure, and its wind and gravity loads are transferred to the floor structure. The curtainwall doesn’t carry the roof load of the building.

Curtainwall Systems

Most curtainwalls start with an aluminum, steel, or composite metal frame, and systems can range from standard options to specialized custom walls.

  • Stick-built systems are built piece by piece on-site, with curtainwall frames (also known as mullions) and glass panels installed and connected to each other piece by piece as construction goes up.
  • Unitized systems require the assemblage and glazing of larger units to be completed at the factory, then the completed modules are shipped to the building site to be erected and connected.

These systems are engineered to allow microscopic movements of the glass panes in their frames, to account for shifts in the building’s structure due to wind or thermal influences.


Both unitized and stick-built systems can be utilized as interior or exterior glazed systems. Exterior glazed systems require the glass panels to be installed from the exterior of the curtain wall and will require swing stage or scaffolding access for repair or replacement. Interior glazed systems are designed to be serviced from inside the building and access can be built into the construction.

Water Resistance

The curtain wall may be made moisture resistant by employing either a pressure-equalized rainscreen system, which is designed with an air barrier to be water tight and capable of shedding water away from the surface with minimal penetration. Water-managed systems do not have an air barrier, and instead use strategically positioned “weep holes” to drain away any water which penetrates the glazing.


A properly designed, glazed, and installed curtainwall provides a sleek, aesthetic look to the building it is part of. Curtainwall glass can be tinted or mirrored and installed in custom designed mullions which create a distinctive sightline. Shadow box construction can be implemented to create the appearance of depth behind the glass by incorporating reflective metal sheets into the curtainwall behind the glass panes.

Curtainwall can be utilized in any type of building, from a hospital to a car dealership to a hotel to an opera house. The style fits elegantly into almost any neighborhood, providing a pleasing aesthetic that is impressive without being unduly imposing. Contact Perspective Glass for a quote for your latest project today.