Biomimetic Building Envelope
Location: USA
Inspiration: African Reed Frog/Hercules Beetle
Creator: Daphne Fecheyr-Lippens & Pravin Bhiwapurkar (2017)
Status: Conceptual
Function: Humidity Control 
, Limited heat gain
Organism strategy: The African Reed Frog copes with the hot/dry season by changing its coloration to a reflective white and inducing naturally reflective crystals to grow on its skin. It also optimizes its position to minimize direct sun exposure. In a wet season, the frog again alters its skin to accept the available water.
The Hercules Beetle also changes color based on the presence of rain/moisture and has a spongy material on its surface that absorbs water.
Design strategy: A facade system was developed to mimic these systems for improved building energy efficiency. The external facade reflects a high proportion of light to decrease heat gain. Air entering the building passes though additional layers of hydrogel and other materials to dehumidify and cool it further. The cooling element can transfer heat to the building water heater system. Finally, a small HVAC unit does the final conditioning and distribution of air within the building. Early results show a reduction of 66% in the energy use intensity of the space condition system.
Visual by Fecheyr-Lippens & Bhiwapurkar (2017)
Ceramic Panel Facade
Location: –
Inspiration: Ticks, Earthworms
Creator: Eleftheriadis S.& Yannan, S. (2012)
Status: Conceptual
Function: Humidity Control
Organism strategy: Earthworm bodies consist of a semipermeable membrane. Due to osmotic pressure, its body will attract water molecules from the soil, functioning as a dehumidification system.
Brown ticks can detect high humidity, and in response, they release a hydrophilic solution. This solution absorbs humid air, allowing the tick to swallow the collected water.
Design strategy: Inspired by the salty solution secreted by ticks, researchers have developed a material that absorbs water vapor from the air, providing an alternative dehumidification system.
Using a dehumidification chamber and rotating panels that contain the material, this system forms the ‘membrane’’ as seen in Earthworms. In future applications, this system can be integrated into a building’s skin to control the humid inlet air.
Visual by Eleftheriadis S.& Yannan, S. (2012)
Hydro Canopy
Location: –
Inspiration: Frogs, Tree Canopy
Creator: MMA-rchitecture
Status: Conceptual
Function: Humidity Control , Limited heat gain
Organism strategy: Anurans have developed a self-cooling mechanism. Their skins contain several mucous glands that secrete a substance that will spread out on their body. The mucous prevents dehydration and aids with body temperature regulation.
In tree canopies, a dynamic gradient of leaf density and size allows for optimal solar energy exposure and wind flow adaptation
Design strategy: This facade system responds to climate conditions using passive control strategies. It consists of three layers. Layer one and two are mobile and adapt to environmental conditions, as seen with tree canopies. They regulate wind flow passage and provide solar protection. The third layer is inspired by the anuran mucous glands and is located in the inner part of the module. This layer functions as an air cooling system. It consists of dynamic bags that contain capsules with stored water, which is released as the bag contracts. This way, hot air passing through the module will be cooled and humidifed.
Visual by MMA-rchitecture.
Hygrothermal Louvers
Location: –
Inspiration: Biological Tissues
Creator: Aletheia Ida Design & Arhitecture
Status: Conceptual
Function: Humidity Control , Limited heat gain,
Light Optimization
Organism strategy: As seen in biological tissues, hydrogels are capable of maintaining their structure while being predominantly composed of water. When enriched with other molecules, hydrogels can respond to external stimuli in a similar manner as biological tissues.
Design strategy: This double skin facade containing hydrogel executes several processes; control of indirect natural daylight, air intake, and filtration, insulation for heat resistance, and water collection. These effects are achieved through additional features such as a titanium oxide nanometer powder coating and a PM2.5 filter.
Keywords: Air filtration
Visual by Aletheia Ida Design & Architecture
Water Reacting Panels
Location: London, UK
Creator: Royal College of Art
Status: Prototyped
Inspiration: Pine Cone
Function: Humidity Control
Organism strategy: Pine cones have slender scales that open up in dry conditions to disperse seeds via the wind. When humidity rises, the scales curl up to prevent ineffective seed dispersal.
Design strategy: Veneer combined with nylon or polyester creates a bilayer material that mimics the outer- and inner layers of pine cones. This material detects humidity levels and changes its shape automatically.
Visual by Chao Chen
