With any complex design or building issue, a team effort is likely to be the most appropriate approach. The combined expertise of the design team, the product supplier and the installation subcontractor is often needed to ensure all issues are resolved and all details considered.

Waterproofing the roof, gutters and roof terraces of the Auckland Art Gallery was tackled in this way. Good communication between the main contractor Nuplex Industries – the waterproofing membrane supplier, and Auckland Waterproofing – the specialist waterproofing applicator, was established early in the project.

A Nuplex modified reinforced bituminous torch-applied membrane system from French manufacturer Soprema was specified as a double and triple layer system to most roofs of the gallery, often beneath the metal roofing, and to all roof gutters. It was also applied to the outdoor seating area.

With any complex design or building issue, a team effort is likely to be the most appropriate approach. The combined expertise of the design team, the product supplier and the installation subcontractor is often needed to ensure all issues are resolved and all details considered. Waterproofing the roof, gutters and roof terraces of the Auckland Art Gallery was tackled in this way. Good communication between the main contractor, Nuplex Industries, who imported the waterproofing membrane, and Auckland Waterproofing Services, who supplied and laid it, was established early in the project.

Nuplex imported a modified reinforced bituminous membrane system from French manufacturer Soprema, which was laid on most of the roofs of the gallery, in many cases beneath the metal roofing, and also lines the guttering. In addition, it was used in the outdoor seating area of the café under the paving, to waterproof the ground floor roof. Double and triple layers of modified reinforced bituminous membrane provide concealed waterproofing on the North and East Sculpture terraces, creating a waterproof roof for galleries on the floor below. 

The product is visible only on the curved roof of the East Gallery and the flat roof close by, which feature almost 3000m2 of the membrane. Bruce Knegt of Auckland Waterproofing Services says particularly complex detailing was needed as the membrane was laid over and under the roof battens. Nuplex and Auckland Waterproofing Services offer warranties of up to 25 years on this product.