The new home stadium of Athletic Bilbao meets the most stringent category 4 UEFA requirements and will offer space for up to 58,000 spectators. The façade and roof form an elliptical shell made of white and transparent films. The project is split into two parts - the roof is fitted by Vector Foiltec, the façade by IASO SA. The façade is made of a tensioned single ETFE layer inscribed in a twisted steel frame.
Sustainable and very resistant
The roof constructed by Vector Foiltec forms several layers of film within an aluminum frame to create a cushion that retains its shape with compressed air. Sustainability of the system is certified by the Texlon® EPD, the first environmental product declaration for transparent building cladding systems. NOWOFLON® ET films have a service life in excess of 30 years, even when exposed to extreme climatic conditions. The films do not require any plasticisers and do not break even when exposed to direct sunlight. No cracks are therefore formed that could harbour bacteria or fungi. The material is so smooth that just a rain shower is sufficient to clean it.
The foils are extruded by Siegsdorf, Germany based specialists Nowofol Kunststoffprodukte GmbH & Co. KG. NOWOFLON® ET 6235Z films are produced in a thickness range from 12-300 micrometres. The company has the production capabilities to produce films that are either transparent or in almost any RAL colour. Dyneon ETFE is Nowofol's material of choice. This high-performance material from the fluoropolymers family affords virtually universal chemical resistance and meets the B1 fire class criteria (according to DIN 4102) or Bs1do EN 13501-1. Even fireworks that are set off illegally inside the stadium will not set the roof on fire.
Textile architecture on the advance worldwide
In addition to transparent foils, architects worldwide for new roof constructions in numerous new stadia also rely on translucent glass-fibre membranes with a coating made from 3M Dyneon PTFE. In contrast, with the highly transparent foils made from Dyneon ETFE, membranes diffuse light and mitigate the impact of solar radiation.
The continuous further development of coating systems and substrate materials enables Dyneon still to expand the application spectrum of these membranes further. The brilliant sealing layer made from thermoplastic fluoropolymer materials therefore improves the visual appeal and weldability. The light surface weight between 500 and 2,000 g/m² and the high tensile strength make it possible for architects to achieve wide spans.
Multitalent "smart membranes"
A polyester fabric coated with 3M Dyneon THV is a completely new combination of materials. The comparatively cost-effective PET offers extremely high tear strength and is ideal for mobile structures thanks to its buckling resistance. In addition to protection against wind and weather, further functions can be performed, such as heat regulation with the help of "smart membranes" developed by scientists at Dyneon. A modified fluoropolymer coating therefore prevents the spaces beneath the roof structure from heating up more than necessary in the event of high levels of solar radiation. These "low E" coatings are able to reduce the necessary cooling capacity of air conditioning units by up to 30% in tropical regions.