What are the main differences between unitized and stick curtain wall systems used in Singapore’s commercial towers?

Unitized and stick curtain wall systems are two prevalent approaches for glazing high-rise commercial towers in climates like Singapore, and both have distinct project advantages that influence choice for developments in the Middle East as well. Unitized systems are factory-assembled modules that include glazing, framing, and gaskets delivered to site as complete panels. Because they are pre-glazed and pre-sealed under controlled factory conditions, unitized systems typically provide superior water-tightness, consistent thermal performance, and faster site installation — a major benefit for tight schedules in downtown Singapore, Dubai Marina, or Doha’s West Bay. They also reduce on-site labor intensity and exposure to high humidity or dusty seaside conditions common in Abu Dhabi. Stick systems are assembled piece-by-piece on site from mullions, transoms and infill panels. Stick is advantageous for projects with budget constraints or where transportation of large modules is problematic — for example in congested urban plots in Amman or older districts in Cairo. Stick systems allow easier late-stage design changes and in-situ adjustments, which is why some renovation and retrofit projects across Riyadh and Kuwait City prefer them. Performance-wise, a well-detailed stick system can match unitized thermal and acoustic metrics but demands stricter site QC and skilled installers to ensure seal continuity in humid coastal sites. For curtain wall selection, developers in Qatar and Singapore weigh module size limits, crane access, façade tolerances, and façade performance targets; unitized is often chosen for premium towers seeking tight tolerances and rapid enclosure, whereas stick remains relevant where phased installation, cost control, or transportation constraints dominate.