Over the past ten years the façade has grown from a defensive climate separation-construction to a much more active and complex membrane, that as an interface takes care of the separation and transition from outer climate and inner climate.
 The new office of ING Group will be equipped with a second skin façade
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New façade-concepts provide façades that actively anticipate the difference between outer- and inner climate and that manage the inner climate together with the building installations. Not only does the demand of the designers for a transparent building-enclosure play a roll in the development of these facades, but also the strongly changing energy balance in many offices (by the increased heat production of miscellaneous machines many buildings currently deliver net heat) and the demand of many users for an individually adjustable climate and a clear view. A notable characteristic of these façades is that they actually co-operate with the installations in a building or even integrate with them to such a level that these facades become part of the installation. Although it seems contradictory the result can be that extra installation techniques are used to be able to realise an energy friendly building that can guarantee a decent inner climate.
A second-skin façade is factually a reversed climate façade: a ventilated air cavity between an inner sheet of insulated glass and an outer sheet of (usually hardened) single layer glass. A sunscreen is fitted in the air cavity, directly behind the outer sheet. Buildings in which such a façade is used are, amongst others, The new ING head office in Amsterdam (Meyer and Van Schooten), Green Building (Future Systems) and the office building in Götz (Webler + Geisler). The advantage of the second-skin façade is that the cavity can be naturally ventilated and that (inside) windows can be opened to ventilate without affecting the system too much. Another advantage of such a second-skin façade is that with tall buildings windows that can be opened by users can be applied without causing wind hindrance.
A disadvantage of a second-skin façade is that they often require an enormous amount of high-skilled techniques (not only in the façade itself but often also additional as building installation for peak loads) so these façades are often substantially more expensive than more traditional façade solutions. Only if less strict comfort-demands are used then much less extra installations can be sufficient and a second-skin façade will then, energetically seen, quickly have more advantages.
However the second-skin façade can quickly become more advantageous when in the not too long term the usage of new developments (photovoltaic cells, micro-installations and electronically manageable glass-coatings) can turn façades into a source of energy. Moreover it is to be expected that climate installations and façades will become increasingly more able to react on a local level to changing loads and demands of users by using small (cheap) sensors and micro-control techniques.
The future of smarter façades is to the sensors.
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