/// Rammed Salt Wall
IMAGINED BY: H. Techen, T. Auer, U. Knaack, T. Klein, M. Bilow and A. Compagno
KEYWORDS: salt, material, dehumidification, cooling, façade
Building in humid climates like that of Abu Dhabi requires the exterior air to be dehumidified before it enters the building to provide comfortable indoor climate conditions. Its crystalline structure gives sodium chloride (common salt) hygroscopic properties; meaning it draws water. Salt is a by-product of seawater desalinization.
The concept is based on the idea to use salt in a structural as well as building physical manner to create solar-powered dehumidification in combination with natural ventilation.
This would result in highly energy efficient building operation. Due to the coarse structure of its crystals, salt can be compacted layer by layer, similar to rammed earth, and can thus be formed into massive wall elements. If used as exterior walls, the salt walls can be perforated. A glass panel installed on the outside provides protection against the weather and promotes the air in the facade gap to heat up, which in turn furthers dehumidification. Since warm air rises, it can easily be guided into the building and through the salt wall (breathing wall). Inside the wall, it can be conditioned as needed (supply air/cooled and dehumidified or exhaust air/heated and humidified).