The humble curtain wall spandrel, often unexciting and without receiving much attention, can be a dynamic and complicated element of curtain wall design that requires focus beyond simply stuffing insulation to meet local thermal performance requirements.

Traditionally a relatively simple construction of insulation sandwiched between an external and internal finish separated by a pressure sealed air gap, performance aspirations are normally set by budgets, climate and the compliance strategy of the design team. Commonly occupying a relatively small percentage of the overall curtain wall area, spandrels…