Jonathan Lowy from VMZinc explains how zinc, in the context of its long heritage as a familiar material on Parisian roofs, is slowly becoming in vogue in the UK for specifiers on mid-rise urban residential projects
Zinc has a long history of association with mid-rise residential projects. It was, after all, Baron Haussmann`s grand project to rebuild Paris in the middle of the 19th century that gave a massive boost to the use of the material not only for mansard roofs, but also for taking rainwater off those roofs. Slightly ironically, one of the traditional Parisian gutters is called a ‘cheneau a l`anglaise,’ translated as ‘English gutter’!
Fast forward to 2022, and certain architects had begun to make zinc a more common sight in contemporary-designed urban residential schemes in England. In Beckenham in south east London, Stolon Studio designed six dwellings using timber frame structures, clad in colourful cementitious planks. The zinc roof (of Anthra-zinc Plus standing seam panels installed by SH roofing) features easily-installed PV panels using seam clamps, which blend into the roof.
Archway Road in north London, designed by pH+ architects, also has a colourful aesthetic. However this time it is achieved by combining Pigmento Red standing seam zinc wall and roof panels with vibrant red brick; some of which had been retained from the original structure. The result is a mixed use building with 25 apartments, with the zinc installed by metal cladding specialist Full Metal Jacket.
In the Old Market conservation area of Bristol, Arturus Architects extended a block of 31 small flats outwards and upwards, to become an elegant building housing 63 larger flats. Again, a combination of brick and standing seam zinc were used on the facades. The design does also capture some of the character in a modern take on the mediaeval gabled street frontage. Here both pre-weathered Quartz-Zinc and Anthra-Zinc are used, and as in Parisian examples, all of the rainwater is dealt with using matching zinc gutters, downpipes and hoppers, fitted by Architectural Metal Roofing.
Back in south London, Shed KM worked with Greenwich council to create a development of one and two bedroom flats on old garage sites. This affordable housing is 100% for social rent but still uses a number of elegant design elements to create attractive homes including large picture windows and durable materials such as Pigmento Red zinc standing seam panels on the facades.
And in Paris itself, while much of the city centre continues to respect Baron Haussmann’s original designs, just outside the centre there are a number of residential developments that have used zinc in a more contemporary fashion. These include the Carre Seine by Pietri Architects, a group of new seven storey blocks that accommodate a 175-bed hotel and 69 flats.
As with the mansard roofs of Paris, all of these projects benefit from the attractive aesthetic of zinc roofs and facades and indeed its durability, which the BRE estimates at 100 years in the Environmental Production Declaration EN 15804. At the end of this long service life, zinc is also 100% recyclable – in western Europe over 98% of old roofing zinc is recycled.
Pre-weathered zinc comes in a wide number of attractive finishes, but for these to be successfully transformed into a finished roof or wall, not only must correct design be followed, it is imperative to use skilled specialist installers. It is for this reason VMZinc works with partner VMZinc@Work installers, who have a known track record of successfully installing the material, and can provide a 50 year material warranty.
Last but definitely not least, while fire protection has always been important, it has for obvious reasons been under increased scrutiny and focus in recent years. Zinc is non-combustible following EN 13501, and applying certain coatings and finishes can take this to a limited combustibility rating of A2. By using a galvanised steel deck and stone wool insulation, zinc can be used on high-rise residential projects. Furthermore VMZinc standing roofing and cladding systems show no flame spread or penetration following Brooft4 testing.
Much of this performance is summarised in a BBA certificate for a non-vented warm structural roof, while the more traditional zinc systems follow EN BS 501 and BS Code of Practice 143-5. As a firm we offer office-based RIBA-accredited CPDs to support specifiers, so please do not hesitate to contact us for more information.
Jonathan Lowy is operational marketing manager at VMZinc