ETFE roofs are available as both single layers membranes supported by cable net systems, and cushions made up of 2-5 layers of ETFE sheets. The cushions are kept continually pressurized by a small inflation unit that maintains the pressure at approximately 220 Pa, thus providing insulation.
Transparency ETFE is a naturally transparent material that transmits light across the entire visible light region, that is, 380-780 nm. A single layered ETFE membrane has approximately 85% light transmission, while an ETFE cushion has reduced amount of light transmission property. However, in both cases, the plants and vegetation underneath the ETFE structure thrive and grow well. This is because a large proportion of infra-red light transmitted is absorbed by the ETFE.
Insulation While a single layered ETFE membrane can provide a good amount of insulation, the standard triple layer cushion can provide better insulation. More the layers, better the insulation. This