A manufacturer of electronic security systems wanted a “unique and bioclimatic” building for its new headquarters in Alcalá de Henares
northeast of Madrid. Alarcon Asociados came up with a design in which (expressive) form and (climatic) function work hand in hand. That the
client is also the owner of the building might explain their boldness in endorsing such an unconventional design.
Towards the top of the building, the red coloured in-situ concrete slabs cantilever increasingly farther out. They reduce the direct solar gain on
the facade by about 90?%, making movable blinds unnecessary. In this building for the first time the architects used a self-developed
HOLEDECK floor system with integrated hollow spaces in which all building services could be routed. That saves around 50 cm of building
height per floor, because suspended ceilings were not needed. With their enormous spans of 12 metres between the piers and their almost
complete symmetry, which is only disturbed by the outdoor stairs on the southwest facade, the 1000 m2 office floors can be arranged without
restrictions. The stick system facades made of timber have a glazed percentage of 50% and opaque spandrel panels with 100 mm mineral wool
insulation. On the exterior, these are faced with 0,8 mm gold-coloured anodized aluminium and on the interior with oak panelling.
Particular to this building are the diagonal buttresses on its centre lines and corners which continue upwards in powerful piers with V-shaped
cross-sections. All vertical air ducts, as well as the heat exchangers for the intake and exhaust ventilation, are contained within these structures,
which Alarcon Asociados call the “noses” of the building. The intake air is drawn in from above the roof, then sent underground through eight
earth pipes (one per pier, each 180 metres long) and finally back through the piers to the office levels. The exhaust air also flows through the
piers and then out over the roof. Due to the preconditioning of the air and the automatic nightly cross ventilation, no conventional air
conditioning system was needed. To heat the rooms, the concrete floor slabs can be thermally activated by means of inlaid piping. Heat is
mainly provided by solar collectors on the roof, with a gas boiler serving as back-up system.
The architects calculate that the building consumes 40% less energy for illumination than a conventional building. The absence of moveable
blinds and the shading provided by the cantilevering concrete floors, they say, should help minimise the use of electric light during daytime.
Artificial lighting is provided exclusively by LED-luminaires with a basic lighting of 200 lux, but the brightness can be increased directly at
workspaces to 500 lux if needed.
Project: R+D Headquarters for LOGYTEL
Architects: Alarcón + Asociados
Location: Avda. Punto Es, 4. 28805 Alcalá de Henares, Madrid, Spain
Associated Architect: Cristina álvarez
Project Year: 2012
Photographs: Pablo Cruz, Luis García Craus, Courtesy of Alarcón + Asociados
Project Area: 4,700 sqm
Collaborator: Sara Rojo, Pablo Cruz, Carlos Tomas
Quantity Surveyor: Jose María Rife Beltrán
Structural Engineer: Jorge Conde, IDEEE
Services Surveyor: Manuel Aranda