advanced building skins 14 | 15 June 2012 - lamp.tugraz.at - Graz ...

Prof. Dr.nat.techn. Oliver Englhardt
Institute of Building Construction
Graz University of Technology
Copyright © with the authors. All rights reserved.
The Inner Skin of the Ventilated Facade
Cristina Pardal, Dr. architect
School of Architecture of Barcelona, University Polytechnic of Catalonia, Spain.
cristina.pardal@upc.edu
Oriol Paris, architect
School of Building Construction of Barcelona, University Polytechnic of Catalonia, Spain.
oriol.paris-viviana@upc.edu
Ignacio Paricio, Prof. Dr. architect
School of Architecture of Barcelona, University Polytechnic of Catalonia, Spain.
Summary
Two highly distinct building systems live side by side in conventional ventilated façades. Even
though outer skins have reached a high level of technological sophistication, inner walls are mostly
shackled to tradition.
This study focuses on the development of a prefabricated panel to meet the functional needs and
specifications of the inner skins of ventilated façades. Panel design depends on the grouping of the
basic inner skin functions.
The most interesting solution is a concrete sandwich panel with two very thin exterior layers made
of UHPCFR with an XPS core. This proposal offers all the required functions and can be
optimized for each situation through the specific design of the materials.
Keywords: ventilated façade, prefabricated, sandwich, building skins.
1 State of the Art
1.1 Ventilated Façades
Ventilated façades are all those enclosures that resolve the issue of waterproofing by providing a
continuous drainage cavity that underlies the entire skin of the building. By definition, these drainage
cavities are encapsulated between two membranes: an outer skin, which typically exhibits open seams,
and an inner skin.
Given that the enclosure must ensure a baseline level of comfort, which cannot be compromised,
numerous functionalities are required of each of these two skins.
Other than waterproofing, some level of sound attenuation and the ability to dissipate direct radiation
via convection inside the cavity, the remaining requirements are delegated to the inner skin of the
façade.
1.2 Empiricism and Rationalization
Two highly distinct building systems live side by side in conventional ventilated façades. Thus, even
though outer membranes and the mechanisms used to attach them have evolved greatly in recent years
and have reached a high level of technological sophistication when dry-assembled by specialists, inner
membranes are still shackled to tradition.
Masonry, either in the form of ceramic units or concrete blocks, is the technique typically used for this
inner skin. It requires a specialized tradesman: a skilled, experienced mason capable of joining
- 1 -