Low-span lightweight membranes in housing : environmental and structural potentialities

Abstract

Textile membranes are usually used to cover big spans with complex geometries, using the special properties of the Hypar (Hyperbolic paraboloid). However it is possible to use membranes on small external façades and coverings, with low spans, not only as sandwich panels, but also as a junction of small Hypar modules. Like this the mechanical special properties of this geometry can be well explored, allowing a very small weight and thus a good environmental performance, compared to conventional façade and covering solutions, on a comparable thickness. Apart from this, the research on membrane materials for thermal regulation, allows to extend its possibilities in order to fulfill contemporary demands of comfort. In the outer skin, architectural membranes can be used as passive systems, for heating (promoting greenhouse effect) and cooling (shading or even evaporative cooling), as well as allowing some transparency, and thus also natural lighting, specially important on south and north facades. A prototype based on this concept is now under construction on Azurém Campus of the University of Minho, adapted for research on external façade systems as well as for coverings of small spans. This solution will be presented from its mechanical and structural concept, as well as its embodied energy and thermal / lighting performance, in comparison with conventional systems.