San Mamés Stadium

  • Date
  • 2014
  • Location
  • Spain, Bilbao
  • Size
  • 19,115 m²
  • Sector
  • Sport, Leisure
  • Structure
  • Steel
  • Application
  • Roofs
  • Architect
  • ACXT


The new roof of the San Mamés football stadium forms several layers of foil within an aluminium frame to create an inflated panel that retains its shape with compressed air. Vector Foiltec was contracted to undertake the detail design, manufacture and installation of the Texlon® ETFE cladding cushions to the stadium roof. It was absolutely critical to work very closely with the project architects and engineers at IDOM on every aspect of the final solution to ensure full compatibility with the design intent.

Vector Foiltec’s principle contribution to the design was in three areas; the development of a bespoke aluminium alloy frame and seal system to secure the perimeter of the Texlon® ETFE inflated panels to the supporting steel structure, Finite Element analysis and system engineering of the ETFE inflated panels to optimise the mechanical performance of the ETFE cladding and development of foil and print arrangements to effect a subtle but continuous reduction in solar transmission through the roof canopy as you travel from the inner edge of the roof overhanging the pitch to the outer edge over the uppermost tier of seating.

The performance requirements for solar transmission through the Texlon® ETFE cladding were complex and challenging. Generally it is important for modern sports stadia in which events are televised that complex variegated shadows are not cast on the pitch by over-hanging roof structures as this interferes with the capacity of the television cameras to track play across the pitch. Light transmission should therefore be diffuse to prevent the formation of bold demarcated shadows by the roof structure. Vector Foiltec has extensive know-how in this field and was able to provide a technically superior yet economic solution.

In the case of the San Mames stadium it was also important that the portion of the canopy immediately overhanging the pitch be as transparent as possible to ensure that the maximum levels of sunlight fall on the pitch during the winter months to maintain grass growth. Conversely the outer section of the canopy covering the highest tiers of seating needed to minimise solar transmission to ensure user comfort during the summer months when heat gain from the sun is at its highest. These conflicting requirements were achieved by the use of differing combinations of clear and print foils and foils with a bespoke embodied inorganic pigment developed by Vector Foiltec within the panel build up as you pass across the roof canopy from the inner to the outer edge – ensuring enhanced ambient comfort.

The construction process was divided into two phases over two seasons enabling Athletic Bilbao to play their home matches at the old stadium while the new stadium was undergoing construction on the same site. Completion of the first phase meant that the team could host matches in the new stadium while the demolition of the old stadium paved the way for completion of the final phase. Adoption of this inventive construction technique meant that Athletic Bilbao did not need to play their home matches at a different stadium, a fate faced by other teams during similar reconstruction procedures.

Structural Awards 2017 for the Stadium Cable Roof Extension

The extension of the roof of San Mames football stadium (Bilbao, Spain) has been build during summer break in 2016. This Texlon® ETFE extension now received the Structural Awards 2017. Learn more about the Awards and find the detailed Judge’s statement here.



A great video about San Mamés extension by IDOM. Click here to go to vimeo.