Criteria to Select between Stick and Untised Systems

As a rule, there are two most important criteria to make a choice between stick curtain wall systems and unitised curtain wall systems:

•Do the panels are highly repetitive and can be done massively in the factory? – If yes, go for using the unitised system
•Does the panel need to allow big differential movement between supports? If yes, go for using the unitised system.

Generally speaking, a decision between both is often not easy. It depends on architectural design and how complex and high a project is. The main criteria are based on the design pattern and the location of the building. Besides, weather and site conditions are the main drivers. Another factor in planning is the repetitiveness of the surface. Are balcony slabs or setbacks in the building complicating the reach and the installation? Are the assumed building movements possible with a stick construction and is structural glazing a requirement? These initial questions will narrow down the options to further evaluate cost impacts and efficiency. The project’s location is vital to understand whether a qualified installer and curtain wall suppliers are at a reasonable distance to provide technical expertise. On-site and off-site assemblies have both their advantages and disadvantages.

In practical construction, building changes can be accommodated within a stick system onsite that is easier than a unitised panel. Once the panel is assembled brackets and slabs have to be accurate in the designed position to receive the pre-assembled bracket while a stick profile can be adjusted.

In general, there are several considerations for you when you will make a choice between a stick and a unitised curtain wall as below:
•Budget: There is a difference in curtain wall cost between stick and unitized system, which is typically reflected in low budget projects where the stick system has this advantage versus the unitise one.
•Building configuration and shape: For example, a unitised system will have a distinctive advantage on a high rise building with a large level of repetition, while a stick system will be more suitable for a podium with a complex design and low level of repetition.
•Performance: There are considerable performance and quality levels of a unitised system versus a stick system that relies on the site workmanship for the correct installation.
•Time constraints: In some cases, there is a tight construction schedule to have material installed on-site as soon as possible due to time and commercial reasons. In that regard, that gives an advantage to the stick system, because they are “by the self” and the materials can be obtained faster for curtain wall structure. On the other hand, a unitise system will help to close floor by floor much faster and allow for other parties to work in the building interior.