Many new studies and projects are adopting the concept of the ventilation within the building envelope. This concept appears in different names like breathing walls, ventilated double façade or skin that breathes. An ingenious idea to renovate an old building in the center of Shanghai was developed by covering the existing windows with an inflatable exterior skin made of white antibacterial technical outdoor nylon. Building with inflatable material is not a new approach and is usually used for temporary structures however the idea of covering an existing building with these materials involve some environmental aspects. The big air cavity between the old façade and the new skin will increase the overall thermal resistance of the building envelope.
The designers described this cavity as a microgreen house that exchange air with the interior spaces to provide fresh air and circulate it through the green area within the bubbles. In order to decrease the energy required to circulate the air, an automated system was designed to control the ventilation by making it works at its minimum capacity when the interior spaces are empty. When the people are in the office, the exterior will be fully inflated to keep the ventilation at its high levels. The main problem of this structure is the lack of the view since the bubbles cover the entire façade. The bubble skin is an attempt to find an alternate for the double skin façade that is built from two layers of rigid curtain walls and making it more flexible and interactive with the interior space.