Hygromorph Skin


Casestudy conducted at the breathing skins Workshop 2018 led by Prof. Petra Gruber, Prof. Christiane Sauer and Dr. Lorenzo Guiducci.

The work has been published in:

Ariana I. K. S. Rupp, Thibaut Houette, Facundo Gutierrez, Lorenzo Guiducci, and Petra Gruber "Breathing skins workshop: A hands-on investigation of bio-inspired foldable structures for temperature and humidity control in buildings", Proc. SPIE 10965, Bioinspiration, Biomimetics, and Bioreplication IX, 2019

Atem / Breath
Gestalterische, ökologische und soziale Dimensionen / Morphological, Ecological and Social Dimensions
Edited by: Linn Burchert and Iva Rešetar

Hygromorph Skin is a study on combining curved line folding with hydroactive material inorder to explore concepts of self shaping, adaptive surfaces.

This design envisioned autonomous regulation of the inner climate of a building that is realized in a passive manner. Hybrid textile-laminates (textile material systems combining a swelling hydroactive layer and a passive layer) could be a future solution as paneling façade elements and would allow for water absorption and evaporation for cooling façades and spaces. Curved paneling elements could have a bi-layered base with a hygroscopic material facing the building and a passive layer facing the outside. When the flap is oriented to the outside it forms a concavity that eases collection of excess humidity into water and transmits it onto the inside layer.
The inside layer swells and forces the flap to rotate towards the façade, in a closed state. A reservoir of absorbed water is now in closer proximity to the façade. When the weather becomes hot and dry, the panel loses moisture thus cooling down the space in contact with the façades. While drying, the hygroscopic layer shrinks, thus bending outward and causing the flap to rotate back to the outside. The open state is more exposed and allows for augmented evaporative cooling. Once the weather becomes humid, the whole cycle starts again. A rigid grid around the panels, slightly compressing the bilayer base of each panel, could force the panels into one of the bent configurations and render the system bi-stable: the system would transition between open and closed state through a snapping instability. Bi-stability could be advantageous because it could introduce a delay in the response of the system to changes in environmental humidity, thus allowing for a better control of the panels operative cycle.