Standing Seam under Green at St. Martins-in-the-field
The new Sixth Form and Gymnasium Block at St Martin in the Fields Girl’s School is an interesting and impressive roof
construction, both visually and from a technical point of view. Armaseam standing seam roofing, ZinCo Green Roof
technology and Skyline Fascia/Soffits were used combined to provide an integrated roofing solution, all supplied by
The original roofing material specified was to be standing seam aluminium, however, Planning Officers expressed concern
at pre-application stage that there may be some adverse response from adjacent residents. The Architects came up with
an alternative solution and proposed that the roof be finished with a green roof system, which the Planners wholeheartedly
approved and encouraged.
The roof build up consists of curved Armaseam aluminium standing seam profiled sheet, which acts as the waterproofing
substrate beneath the ZinCo green roof. Armaseam is a versatile, high performing metal roofing system based on the tried
and tested principle of zipped joints, and is suitable for curved, pitched or virtually flat roofs. Panels are roll formed –
either on site or in the factory – from continuous strip coil to any required length, without the need for end laps. The
result is an integral roof covering with no penetrative fixings or vulnerable joints, providing outstanding performance for
the life of the building.
The curve of the roof profile meant that the ZinCo green roof system had to accommodate falls from 26º at the eaves to
zero at the crown of the building, which lead to the development of a project specific substrate baffle retention system,
which has proven to be highly successful. As the roof slopes were so severe, the decision was made to use sedum mats at
the eaves and gables, to securely anchor the substrate in position and to provide an immediate established appearance to
the vegetation from ground level. Sedum plug plants were used in the field area in order to provide a more cost-effective
solution for the overall planting scheme. The striking Skyline bullnose fascia/soffit configuration gave the roof its
distinctive appearance by contrasting with, and delineating from, the green planted areas.
Full details on Armaseam, Skyline and Zinco Green Roof systems are available on Alumasc’s new website at www.alumascexteriors.
co.uk, including full technical information, CAD downloads and an NBS Specification generator. Product literature
is available by calling Alumasc on 0808 100 2008.