at:length
Disruptors in Facade Technology www.aluprof.eu
The facade industry is quite mature in its lifecycle with aluminium being the most sustainable material to specify for windows, doors and facades. With high performance thermal breaks, it is possible to specify aluminium systems that will help projects reach the Passivhaus standard. But what of the emerging technologies that will influence sustainability and efficiency? Thirty-five years ago CAD revolutionised the way we designed aluminium facades. Here was a system that could easily calculate complex structures, angles and profile lengths making cutting, machining and assembly more cost effective. Later, adding CAD output to CNC machines further influenced efficient manufacture to such an extent that most fabricators now have at least one of these machine centres and design in 3D. BIM is now also filtering down into the fabrication arena which will add further efficiencies in the specification and manufacture of building envelopes. Cutting edge computer technology in construction is looking to AR, or Augmented Reality, mixing both the physical with the digital. Using either front facing cameras on tablets or AR headsets we will be able to see a digital overlay of a structure either on a structure or a structure yet to
complete. This has huge benefits when considering the complexity of setting out and measurement. So not only can the BIM model be used to filter down the product into production, but the AR used on site with the BIM overlay, setting out for the product or facade element, will be achieved more easily and with greater accuracy. Also finding its way into commercial facades is the composite profile for carrying glazed elements both in terms of windows and curtain wall facades. Having similar expansion co-efficients to glass itself, a fibreglass composite has some good insulation properties and can complement a facade which has a structural grid of aluminium. Also known as ‘pultrusion’ the process is relatively new and has of late developed a great deal. The process involves a liquid polymer resin and glass fibre mix being pulled through a heated die which cures the polymer whilst aligning the glass fibre strands for optimum strength. This is a process that Aluprof developing for some systems to further enhance our products performance. Active or smart facades are increasingly being designed to optimise our buildings sustainability. At one time we just looked to the facade to keep out the wether and let the light in. More recently insulation has become an important feature in order to reduce heating costs. New facades are beginning to become active, that is, changing with the time of day and weather conditions.
These active facades include such things as automatic solar shading to reduce solar gain, screens which automatically close at night to maximise insulation and automatic natural ventilation systems to purge stale air. Further enhancements will include smart technologies which will harness solar gain, energy from light and wind to become an energy generator for either immediate use or for storage for future use. Possibly one of the most unusual developments is the adoption of the biofacade. Using micro-algae trapped within glazed units offers both solar shading and helps improve interior air quality as the algae grows on the carbon dioxide within the air in the building whilst expelling oxygen in the growth process. Together with this photosynthesis, the process generates heat which can also be harnessed for the buildings use. The systems, known as photobioreactors (PBR’s), has been used successfully in the BIQ House, a five story apartment building designed by Splitterwerk Architects in collaboration with Arup, where an algae facade is used as a shading device. In its infancy, this technology is being considered for much larger high rise developments. 10
