A ZinCo green roof from Alumasc has been specified for a low-energy superstore in Oakham, Rutland. Designed by KPW Architects for Midlands Co-Operative Society, the roof of the £4.5m building features local species of sedum-based plants that will require minimal irrigation and maintenance to create a wildlife habitat. Rainwater is also harvested from it.

The roof is installed over Alumasc’s Derbigum single-layer waterproofing system to achieve the wind load and U-value requirements of the project.

To meet the demands of the fast-track construction programme, the system was mechanically fixed onto the structural deck, with the end and side laps welded by torch application. Hot air welding can also be used.

The roof system is approved by the British Board of Agrément, manufactured under ISO 14001:2004 and EMAS Environmental Management Standards and is fire rated FAA to BS476 Pt3 (EN1187 Pt4) - the highest available.

It is anticipated that the building will achieve a reduction in carbon dioxide emissions from 103kg/m2/year to just 40kg/m2/year.