Zinc, traditionally been used for roofing and rainwater systems, is now being used to clad facades. For zinc roofers, if not exactly a revolution, this paradigm shift brings a major change in work practices.
The turning point of this evolution in the use of zinc corresponds to the arrival, at the start of the 1980s, of preweathered products, first in dark grey and then light grey. These vibrant, sleek new aspects revamped the image of zinc, which, in its natural version, when subject to the hazards of its environment (climate, pollution, orientation…) evolves in a less homogenous manner. So the idea to use this material for facades as well as roofs quickly became a reality, largely due to the fact that the same techniques as for roofing are used.
Architects seized the opportunity to use these more uniform and decidedly contemporary aspects with the intention of showing them off. Widespread use of the standing seam technique also largely contributed to establishing the new preweathered products as architectural products in their own right. Installation of zinc in parallel strips separated by visible ribs creates a highly graphic effect and gives the building a striking appearance. The malleability of zinc also makes it possible to create discreet continuity between the roof and the facade, often by integrating rainwater systems. This control of details is a huge plus architects!
The use of zinc on facades generated less enthusiasm among roofers. In fairness to the latter, they had been masters of the area above the gutter for decades, an area where no one else dared to embark. Like kings in their rooftop domains, they organise their work and use their know-how to install perfectly watertight durable roofs.
So “moving down” to the facade is a radical change for roofers in terms of how their profession is viewed and practised. They now have to affront the street and the view (they can be seen working, the final result will be judged), as well as anticipating an entirely different type of site organisation. What is even more significant for these craftsmen is the fact that the attention given to the aspect of the zinc used on facades is much greater (flatness of the metal, layout of strips adjusted to positioning of windows or edges of the facade). The utmost requirement is no longer absolute watertightness but absolute elegance. So certain roofers hesitate before entering this market segment.
Whereas the facade is the major area of growth for zinc worldwide. For the last two decades, architects have been enthusiastically using these surface aspects (recent coloured preweathered products) and the new installation techniques with prefabricated cassettes and panels. At a time where roofs are being taken over by solar panels (we will be covering this topic in another column), roofing contractors are successfully relying on this new source of growth for their businesses. It goes without saying that the surface of facades is much larger than that of roofs (1:4 ratio for a small collective building).
Roofers have equipped themselves and provided specialised training for workers in this segment. Architects appreciate working with these craftsmen who pay great attention to flashings and elegant details.
This column is in fact an invitation to roofers! Have a look at zinc used on facades. Enhance this growing segment with your skills, especially for surrounds and trims, to which facade installers pay less attention. In short, become specialists in metal building envelopes!
VMZINC Communication Director