How is thermal insulation achieved in double-glazed curtain wall designs?

Thermal insulation in double-glazed curtain walls is achieved through the combined performance of insulated glazing units (IGUs), warm-edge spacer technology and thermally broken frames. IGUs consist of two glass panes separated by a controlled cavity filled with air or inert gas (argon or krypton) that reduces conductive heat transfer. Warm-edge spacers—made of low-conductivity materials—limit thermal bridging at the glass perimeter and reduce condensation risk, improving the effective U-value of the unit. The curtain wall frame includes a thermal break, typically an engineered polyamide or composite element that interrupts the continuous aluminum path and significantly lowers conductive heat flow through mullions and transoms. Continuous insulation, thermal gaskets and minimized metal sightlines further reduce heat transfer. For Gulf applications, we optimize glass thickness, coating selection and cavity width to balance visible transmittance with low SHGC values, ensuring reduced cooling load without sacrificing daylight. Proper edge-seal technology and factory-controlled IGU assembly are also crucial for longevity in high-temperature environments. When these elements are combined and validated through thermal modelling and whole-system U-value calculations, a double-glazed curtain wall delivers the thermal performance required for comfortable, energy-efficient buildings in desert and coastal climates.