The Breathing Skins showroom
A prototype building covered by a “breathing skin” that allows it to use the outside air temperature to adjust the indoor climate has won an industry award.
The “breathing skins” project won the ‘Innovation’ category of the European Polycarbonate Sheet Extruders Organisation (EPSE) annual awards for its use of polycarbonate sheeting from Covestro in the building’s structure.
The project, which was invented by Tobias Becker whilst a student at the University of Stuttgart, centres around a breathing facade skin using transparent solid sheets of the polycarbonate Makrolon.
Breathing Skins showroom
The prototype building is a showroom for testing breathing skins’ facade technology and allowing people to experience it.
The facade is over ten meters long, has an area of 25 square meters and is split into several elements. To reinforce the image of a continuous facade, the load-bearing parts of the sandwich facade elements are all made of solid polycarbonate sheets. The interior has an area of eight square meters and a clear height of 2.4 meters.
Muscle management
Becker says the inspiration for developing a breathing facade skin comes from the idea of ventilating an interior via pore-like air ducts without creating a draft.
These ducts can be sealed pneumatically so as to be airtight by applying a small overpressure to the facade element.
A low-energy compressor controls around 140 pneumatic “muscles” per square metre without any visible technology. Applying a small underpressure widens the reversible air ducts fitted between two perforated, transparent solid sheets of Makrolon GP clear 099 polycarbonate. The sandwich design weighs less than 11 kilograms per square metre.
The more the pneumatic muscles dilate, the more the facade’s appearance changes. Permeability for light and air as well as see-through visibility can be modified locally and gradually. The concept is based on biomimetics, the basic idea of which is to observe nature closely and turn the findings into technical applications.
More than just transparent glazing
Covestro says the showroom demonstrates that polycarbonate sheets can be used for more than just transparent glazing in architectural applications, adding that their mechanical properties and the fact that they are milled during the machining process enable easy integration of controllable elements such as the pneumatic muscles.
The company believes that transparent facades of all building types therefore become a tool for controlling energy management and interior climate.
A video at www.breathingskins.com shows the spatial conditions and the way the breathing facade works.