ETFE cushion envelope
Multilayer ETFE film cushions form lightweight translucent roofs and facades.
Much lighter than glass, ETFE can use frit patterns and transparency to control solar gain. Pressurized air between layers adds insulation.
The system is known from Allianz Arena and the Water Cube, and is also used over gardens and atria.
Welds, clamps, pressure controls, leakage, snow, wind, and condensation make the film inseparable from mechanical systems.
Specifications must define fire behavior, service life, and replacement. Light weight increases the importance of frames and waterproof edges.
