The project was carried out in two phases, with the central area where all the rooftop plant is located completed first, followed by perimeter areas.

The phase 1 roof area at the centre of the roof is extremely congested with plant and a complex network of legacy steelwork, which needed to remain in situ. Following strip out, the roofing contractor improved the roof layout by creating raised areas which were then boarded and waterproofed, along with the field areas, using a full ARBOFLEX® PU roof build-up, comprising ALUTRIX® 600 vapour barrier membrane, ARBOFLEX® PU primer, insulation, and the cold-applied liquid waterproofing system, including the glass fibre matt and U/V topcoat. The tapered insulation also improved drainage. For any steelwork that could not be boxed in, the correct ratio of ARBOFLEX® PU Thickener was added to the ARBOFLEX® PU liquid to allow the system to be taken up the vertical length of the supports, providing excellent protection against water ingress.