
To pay tribute to a spectacular panorama on the edge of the Atlantic Ocean, the architects Renzo Piano in collaboration with the Madrid agency Luis Vidal + Architects, have here favored natural light and lightness; a party that required integrating sun protection into the very design of the building.
To protect collections by guaranteeing optimal visual and thermal comfort to visitors throughout the year, an ingenious combination of Satin 5500, SV 10% and Karellis 11301 fabrics from Mermet has been developed.
When light and transparency co-exist
Built on the seafront, in the Gardens of Pereda, this two-headed building has become a major tourist attraction with its coating of 270.000 ceramic discs.
Placed on pillars at the height of the treetops, two curved buildings of 10.000 m² free the view and offer direct access to the bay from the historic city center:
- the West wing deploys 2.500 m² of exhibition space on two levels, 5 meters high,
- the east wing hosts classrooms, workspaces as well as a 300-seat auditorium whose glass facade to the south reaches 7,5 m in height.
For architects, it was just as essential to:
- bring in as much natural light as possible while controlling glare,
- maintain perfect transparency, both outwards and inwards, to enjoy this remarkable location which multiplies the visual connections with the water and the park,
- protect the works while ensuring optimal thermal comfort for visitors.
Developed and installed by the blind manufacturer Resstende srl, it is the superposition of three Mermet fabrics up to 8 m high (i.e. 300 blinds in total), which has made it possible to meet all these objectives:
- a high-profile outdoor blind (1,20 x 7,90 m) to control light and heat: the Satin 5500 fabric color 0201 White Gray filters 94% of solar radiation to ensure thermal comfort and protects from glare and UV radiation to preserve the works on display,
- two fabrics for indoor application complete the sun protection device:
- to darken and block the sun's rays, the 0,8 x 7,90 m zip blinds fitted with the fine and light Karellis 11301 canvas in 608 Chartreux colors, regulate the light here and allow total blackout,
- to increase the brightness in open spaces, the SV 10% color 0102 Gray White fabric was selected for its ability to diffuse light and its transparency; it was installed on roller blinds 0,80 x 4 m in height.

A project of excellence, fabrics of excellence
Mermet, unique fabrics with their material composed of glass thread
Particularly adapted to the new standards of contemporary architecture and in particular to high bay windows like those of the Botín Center, thanks to their composition, Mermet fabrics are distinguished by:
- their excellent mechanical resistance for tensioning,
- their M1 fire classification which meets the standards of establishments open to the public,
- their excellent dimensional stability even more important for tall bays,
- their remarkable durability with their mechanical endurance test of 10.000 cycles
Satiné 5500, the outdoor sun protection solution
Ally of the facade, the Satiné 5500 fabric presents:
- unequaled protection against heat: up to 96% of solar energy is rejected in external application (gtot of 0,04 with a glazing of reference g = 0,32 and U = 1,1)
- high quality transparency with a clear vision towards the outside,
- ideal visual comfort with very good glare control thanks to its diagonal satin weaving while optimizing the supply of natural light: up to 96% of the light rays are filtered (Tv: 4%)
SV 10%, for transparency and optimal natural light
This braided fabric combines visual comfort and transparency and optimizes the level of natural light. It blocks up to 90% of UV rays and rejects up to 85% of solar energy.
12 colors are available in 3 widths of 200, 250 and 320 cm.
A major project, the Centro Botìn offers Mermet the opportunity to demonstrate once again its unique expertise in terms of sun protection. With fabrics that guarantee an excellent level of thermal and optical performance and that meet all requirements, even in a marine atmosphere, the French company can claim a new prestigious international achievement.