Chapelfield, a ?275 million retail led, mixed use regeneration scheme in Norwich will feature one of Rock Asphalte?s largest ever Flexiphalte triple protection roofing systems, spanning some 13,000m2 . The roofing/structural waterproofing system was specified by Architects BDP (Building Design Partnership). It offers two waterproofing layers underneath a third layer of insulation. Guaranteed to last the designed life of the substrate on which it is layed, the roofing carries BBA certification. The system consists of a Flexiphalte Baryprene membrane fully bonded to the substrate in hot bitumen. A modified mastic asphalt is then bonded to the membrane and overlaid with a layer of insulation.