Curtain Wall Systems: Stick Versus Unitized

In a typical high rise building, one element of its brilliant facade technology is the curtain wall system. A facade comprises of a window wall, curtain walls, and cladding elements, all three of which are the exterior of the building. In a modern building, the curtain wall systems have a structural importance that is just as necessary as the other elements. Thus, proper design, installation, and maintenance are necessary to sustain its functionality, after all, it protects the building from the exterior environment. If you find yourself interested, read further to learn about the functions of curtain walls in buildings as well as the two different types of curtain wall systems.

Functions of Curtain Walls in Buildings

There are at least four functions of curtain walls in buildings, namely air impermeability, elimination of water penetration, resistance to elements, and reduction of solar levels.

Air Impermeability

It is necessary to reduce the emission of carbon dioxide because of heat loss or gain in the environment. It is an environmental concern, after all.

Elimination of Water Penetration

A facade’s fundamental function is water penetration. Since constructing a completely impermeable sealed curtain panel system is impossible, there must be two stages of prevention. First is a complete defense of water, and then a second level which directs and drains out the water.

Resistance to Elements

The cladding system transfers wind actions to the building floors, acting as a linear support. The building cladding systems made of large panels are often one-way spanning. Each of the floor levels then supports only one level of wind load on the building. As for thermal insulation, it is necessary for reduction of both carbon dioxide emissions and energy consumption. Insulation applies to both opaque and transparent portions of the curtain wall system. Lastly, acoustic insulation is just as necessary for both the internal and external environment, especially for a city-centered building.

Reduction of Solar Levels

The curtain wall system reduces solar levels by adding a selective solar control coating on the glass surface. Only certain wavelengths can pass through this coating, such as visible wavelengths of light. Meanwhile, inhibition of UV rays may be desirable, so the surface of the glazing has a UV-inhibiting film.

Stick Curtain Wall System

The stick curtain wall system’s components have to go through assembling piece-by-piece on-site. This system is often ideal for low-rise buildings or smaller regions. After all, exterior access is essential to reach higher elevations. As such, it may require cranes and scaffolding. One advantage of a stick curtain wall system is its low shipping cost and the fact that on-site adjustments are possible. However, this requires high amounts of time consumption and labor costs.

Unitized Curtain Wall System

On the other hand, the unitized curtain wall system involves assembling by interlocking different units from the factory. After delivery, it is already the whole package, since assembly occurs in the factory, not on-site. Furthermore, individual installation of its components is not as essential as the stick curtain wall system.

The floor-to-floor height of the building decides the size of the unitized curtain walls. Thus, it becomes essential to think about the mode of transportation as well as the installation as planning its facade depth goes on.

Contrary to the stick curtain wall system, the unitized curtain wall system is suitable for high-rise buildings. Furthermore, it will not require exterior supports such as cranes or scaffolding. In fact, a mini-crane or a hoist will be necessary to hold its position as installation goes on. The unitized curtain wall system gains the advantage of short construction times and better quality due to the factory manufacturing. However, shipping charges cost higher due to the larger protection during its transportation.


The curtain walls for buildings are necessary for air impermeability, elimination of water penetration, resistance to elements, and reduction of solar levels. There are two types of curtain wall systems, namely, stick curtain wall system and unitized curtain wall system. The former is more appropriate for low-rise buildings, is assembled on-site, and has low shipping fees. As for the latter, it comes with shorter construction times and higher quality, but it has higher shipping costs since it is assembled in the factory.