Engineering and material

Structures made of multi-layered ETFE foils

As the material is not fabric-reinforced, owing to its mechanical properties 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.

The so-called "bubbles" are held in shape by air pressure in the cushions (approximately 300 to 800 Pa). Depending on the cushion geometry and the external loads, the individual cushions can span 4.50 metres, with no other supporting structure. Much greater spans are possible with additional tensile structure reinforcement. The supporting air supply and the control can be largely automated. Custom design concepts can provide the optimum solution for each project.

ETFE-Fassaden- und Dachkonstruktion - IPS-International School in Portugal

ETFE-cushion constructions retain their stability due to a pneumatically-generated synclastic design.


 Base material  Fluorpolymer  
 Total weight (g/sq.m)

 175 or 0.036 lbs/sqft (at 100 μm)

 Tensile strength (N/mm2)

 Longitudinal direction  51 - 58 
(7396-8412 PSI)
 Lateral direction  53 (7687 PSI)

 UV-resistance  very good
 Stain-resistance  very good
 Translucence  approx. 90 %
 Colour  highly transparent
 printing and dyeing possible
 Fire classification  DIN 4102 B1 
 flame retardant
 EN 13501-1 / B-s1,d0