ACXT create an atmosphere closer to that of a home which does away with the axioms of the traditional office building
The architects were not dealing with a project influenced by the pressure of the real estate boom or the need for an iconic brand image. The most pleasant and unique circumstances were set before them: the client was also the developer, the architect, the contractor and the user. The initial aspiration of the assignment was simple: to erect a building that would house the activity of IDOM, while at the same time representing it and becoming as it were a visiting card for clients. The firms culture and way of working should be clear from the building itself. This was an opportunity to turn a building into a showcase of their philosophy. Where could they find the keys that represent a firm like themselves? Taking into account the special culture of IDOM, it was obvious they would have to abandon any idea of it being media approved, short term or of rapid recognition. All these qualities seem to be an obsession which worries many corporations today, who need rapid success and visual appeal. The architects decided to focus their work far from that rationale. They aimed for true environmental comfort, measureable, credible, real and not conditioned solely by its representative or spatial tectonic values.
The objective was also to create a more domestic, porous, ventilated, natural and agreeable working environment; something closer to the working conditions of a home than those of a typical tertiary bubble. The architects had to overcome the classic miseries and limitations of the 20th century office, consequences of its unhealthy attempt to create an artificial atmosphere and an iconic brand image. In order to change those paradigms, a radically new approach was necessary. It was essential to make energy, the load bearing systems, the HVAC, the light, the orientation, the management of water or space and the sustainable strategies the bottom line of the codes over which the architectonic and formal references were to be supported, and not the other way round. ACXT had to forget many references and images, load up with reasons and work with a new premise: the idea is not imposed on reality; the idea is conceived by the needs that reality imposes. An atmosphere closer to that of a household which would do away with the axioms of the traditional office building. A space free from suspended ceilings and raised floors, with wooden openable windows, fabric ventilation ducts, exposed masonry walls, slow propulsion of air at room temperature... in a nut shell: the non - office.
The HVAC based on radiant systems (TABS), using the high thermal inertia of the structure and its post-tensioned concrete floor slabs. An air propulsion system conceived exclusively for slow air renovation through fabric ducts, which can be cleaned and avoid noise pollution. Large structural spans that allow for a flexible distribution of spaces. Sun protection towards the south, and toned down light from the north. The perception of a continuous space both horizontally and vertically. A setting that includes fragments of nature, hanging gardens and green walls. A correct strategy for reusing water making the most of it for visual and acoustic pleasure. A building of reasonable cost and simple maintenance, easy to use and understand, flexible, kind in its presentation, quick upon changes, good, attractive and cheap and maximalist in its aspiration. A hi-tech building with low profile technology, complex in its conception but simple in its resolution.
ACXT wanted a rigorously sustainable building, convinced of the high architectonic return of such an approach; an adequate balance between ecological, economic and social aspects. They pursued the aim of simply being able to work in a healthy environment, free from heat and cold, without any dazzles or toxic elements. All this implies high satisfaction levels and a healthy atmosphere. This dynamic fitted in perfectly with the strategic objective of IDOM, and that is how the user has perceived it: an effort to build new office spaces breaking away from the old guidelines. The building has an HVAC system which must be considered an integral part of the building itself (TABS: Thermally Activated Building System). A number of hydraulic circuits are laid out over the concrete slabs, keeping the temperature of the mass of the whole building within values very similar to those of the surrounding environment. There is no thermal stress. There is no noise or temperature difference between areas. It is the first building of its class in Spain which incorporates this technology, which is already being used in central Europe. The adaptation of this system to the Mediterranean climate, and specially to the particular conditions of Spanish construction methods, have proven to be quite a challenge, research wise, which has finally paid off with the construction of this building.
The high inertia of the system manages to separate completely in time the demand for energy from its production, granting it clear advantages over traditional systems. The energy accumulated in the structure during the day is freed by overnight evaporative cooling. The efficiency of this method cannot easily be matched by any other. Air is renewed in a much calmer way, since temperature is no longer an issue, by means of a textile ducts system. It is a technology that has its origin in the food industry due to its high hygienic and sanitary levels, never before having been applied to an office building in Spain.
Making the most of its clear advantages and researching the system design alongside the manufacturer (KE-Fibertec) to adapt it to its new function, good results have been achieved regarding its salubrity, air quality and comfort, key issues in this type of building. This system contributes a great deal with the energy efficiency factor. The network deals with great flow variations and allows for making the most of favourable exterior conditions to ventilate the interior almost free of charge, without any unnecessary energy consumptions. The use of a natural ventilation system, without any mechanical aid, has been researched. To that purpose, vertical communication atria have been planned, working as great HVAC return air collectors, dispensing with conventional return ducts. When natural ventilation starts, the air propulsion machines stop and the atria continue to work as a return shaft, only this time it drives the air towards the exterior through the discharge systems at the top of the atria, while the new air enters through the openable windows of the offices.
Zero consumption and natural ventilation allow the building to work without any other support when exterior conditions are adequate. Therefore, consumption levels are expected to be so low as to comply with regulations that will follow the new EU Directive on the energy performance of buildings (Directive 2010/31/EU of 19 May 2010), which will come into full effect by 2020. Madrid Idom office was finished in December 2010.
The new IDOM HQ in Madrid represents an important step forward in the field of energy efficiency, comfort and water saving in office buildings.
Firstly, the building envelope incorporates a series of elements designed to minimise energy demand. Its orientation, the optimisation of openings, high thermal insulation, high performance glass, its high level of solar protection and both the green façade and green roof, are just some of the measures that reduce the energy demand by approximately 50%.There is only one totally free way to dispose of part of the excess heat: natural ventilation. The building has several atria for vertical communication that double up also as natural ventilation shafts. When weather conditions are appropriate, they can take over from mechanical ventilation. Having reviewed these aspects, they then tackled energy efficiency. In order to achieve the best efficiency possible, IDOM offices have implemented a Thermally Activated Building System (TABS), in which the structure can withdraw approximately 50% of the excess heat within the building, almost completely cost-free, thanks to hydraulic free-cooling techniques.
Taking it all into account, the office block has a final annual energy demand between 40-50 kWh/m2, which is considered close to zero consumption. With regard to water management, 100% of rain water is collected and reused, whether it be in the watering system, the refilling of flushing systems in toilets or the evaporative cooling system of the structure.