Britomart Transport Centre

BIGGEST PILKINGTON ACTIV™ PROJECT TO-DATE BRINGS TRAINS BACK TO AUCKLAND AFTER 70 YEARS

A multi million-dollar development in Auckland, New Zealand has become the world’s largest project to date featuring Pilkington Activ™ self-cleaning glass. The scheme, which was initiated by Auckland City Council, incorporates three elements: the development of a transport centre, including a railway station built underground; the urban renewal of the downtown area; and the refurbishment of adjacent heritage buildings. It is the largest infrastructure project ever undertaken by a local authority in New Zealand, and the impressive underground railway station is bringing trains into the city centre for the first time in more than 70 years.

Architects Mario Madayag of MML and Greg Boydon of Jasmax created a simple concrete box to house the railway station, which was integrated with the historic former Chief Post Office that formed one of the key elements of the restoration to provide a grand entrance to the transport facility. The Chief Post Office building was then linked to the station by a 28-metre long glass bridge, which takes passengers from the ticket hall into a spectacular vertical glasshouse. The glasshouse acts as a mezzanine above the stairs and escalator leading into the station below.

The glasshouse is built using 1,865 louvres, each measuring 1900mm by 900mm and manufactured from 13.5mm thick toughened and laminated glass, supported by a specially designed and constructed steel structure. Woods Glass designed and manufactured the glazing systems that were specified by Arup Façade. This called for the development of rain traps and wind baffles that would restrict rain and wind from entering the interior of the building, whilst still providing efficient air flow to ventilate the tunnel. A wind tunnel was specially designed and built to test the louvre systems, simulating Auckland’s weather patterns in more than a hundred tests.

Maintenance of this extraordinary structure created a number of questions, not least concerning the cleaning of the glass. The latter was overcome by specifying Pilkington Activ™, the world’s first self-cleaning glass, which was toughened and laminated, and bonded with toughened and laminated clear glass on the inner leaf. Pilkington Activ™ was also used on other external glass areas, including the 200m² of laminated glass used on the glasshouse roof, and 300 steel-framed windows, all produced by Woods Glass.

Developed in the UK by Pilkington plc at the company’s Technical Centre in Lathom, Lancashire, and launched following extensive field and laboratory testing, Pilkington Activ™ will continuously clean the external surfaces of the glasshouse by harnessing the two natural elements of ultra violet light and rain. The dual action of Pilkington Activ™ uses a special, permanent hard coating that continuously reacts with ultra violet light from the sun to break down organic deposits of dirt, with a secondary action that causes rain to sheet on the glass to wash the deposits away.