ETFE-technology – innovative, durable and efficient
Modern architecture is hard to imagine without use of transparent structures for facades and roofs. Besides glass structures, innovative structures made of ETFE foil are increasingly gaining significance.
Ideal applications include sectors where the conventional approach would often be to use glass (swimming pools, water parks, atriums, skylights, zoos, greenhouses and palm houses etc..
Structures made of multi-layered ETFE foils
ETFE (ethylene tetrafluoroethylene) is an innovative material which is used in building as extruded foil with thicknesses from 0.1 to 0.3 mm (100 to 300 µm).
ETFE as non-fabric-reinforced material, ETFE foil is used primarily in the form of air-filled cushions. The foil cushions can be equipped with multiple air chambers to attain low U-values.
Heat from sunlight can be reduced by printing on the foil cushions.
The so-called "pillows" are held in shape by air pressure in the cushions (approximately 300 to 800 Pa – 0.0435 to 0.1160 PSI). Depending on the cushion geometry and the external loads, the individual cushions can span 4.50 meters (14.76’), with no other supporting structure. Much greater spans are possible with additional tensile structure reinforcement. The supporting air supply and the control is fully automated. Custom design concepts can provide the optimum solution for each project.
ETFE-cushion constructions retain their stability due to a pneumatically-generated synclastic design.
|Total weight (g/sq.m)||
175 or 0.036 lbs/sqft (at 100 μm)
|Tensile strength (N/mm2)||
Longitudinal direction 51 - 58
|Translucence||approx. 90 %|
|Colour|| highly transparent
printing and dyeing possible
|Fire classification|| DIN 4102 B1
EN 13501-1 / B-s1,d0
Single-layer ETFE foils
ETFE foils can also be installed in single layers. The material-specific properties of relatively low elastic deformation and high plastic deformation, as well as high ultimate strain must be taken into account when doing so. Normally the foils are supported by thin steel cables (8 – 12 mm, 0.315” – 0.472”). The spacing and layout of the steel cables are specified according to the structural requirements.
Especially high light transmitting capacity of approx. 90% in the visible wavelength range
(from 400 – 700 nm/UV)
High UV transmissibility, depending on the material thickness
Good thermal insulation: U values, depending on the number of foil layers
G value between 0.10 and 0.85 depending on the design and alignment of the printing pattern
Low weight of foil cushions, thereby facilitating light, intricate substructures
Very good mechanical properties: High tensile strength/tear resistance and hail resistance
Flame retardant – ETFE foils burn off without dripping
Low maintenance costs due to anti-adhesive surface with self-cleaning effect
Interesting design options offered by printing, e.g. shading without additional construction
Long service life of at least 25 - 35 years
Cost savings in comparison with conventional transparent roof constructions
By partially coating the foils, it is also possible to produce a shading effect.