Gerard Lighting recreated the bronze lanterns originally fitted on the iconic Sydney Harbour Bridge as part of a project to improve the lighting as well as preserve the heritage character of the structure.
Gerard Lighting is headquartered in Sydney, providing sustainable and innovative lighting solutions to their clients drawn from industrial, commercial, residential and infrastructure segments. The company was commissioned by RMS (Road and Maritime Services) to work on changes to the lighting on the Sydney Harbour Bridge.
When completed in 1932, the bridge’s roadways were lined with distinctive bronze lantern fittings. Unfortunately, the lights produced a glow that was deemed to be unsafe for drivers. The lanterns were removed in the 1950s and replaced with modern fittings. Their historical significance forgotten, most of the lanterns were also unfortunately destroyed.
The current century has seen an increased focus on preserving Australia’s national heritage and historical structures. Owned by the RMS, the bridge’s heritage value is proudly being upheld by ensuring that any changes or modifications required to service contemporary requirements are done in a manner that is respectful to the original architecture. It was decided in 2013 to resurrect the original bronze lanterns to achieve the twin objectives of effective lighting as well as restoration of the heritage aesthetic.
Gerard Lighting sought to create a lighting solution that was both functional and aesthetic while maintaining existing light levels. The new lighting for the roadway, walkway and traffic had to be unobtrusive and hidden from view, while the heritage lanterns needed to produce a soft glow to recreate the heritage feel of the original bridge, all without being a hindrance to traffic.
Using a recast of the original lantern supplied by the RMS, Gerard Lighting created the moulds for the new lanterns at a foundry in Western Sydney. Bronze was chosen as the preferred metal because it was durable and didn’t require painting.
Borosilicate was chosen as the glassware because of its high durability as well as resistance to expansion and contraction with temperature changes. The heritage fitting is only designed to glow without contributing to the road lighting. Borosilicate flat glass panels were held in place with highly durable compounds to allow the lanterns to remain watertight. Gerard Lighting incorporated an additional visor over the module to counter any internal condensation. They also recommended that the RMS include two bronze breathers to ensure pressure equilibrium, which is very important to maintain a dry internal environment in the fitting.
For the lighting, Gerard Lighting used a carcass heritage fitting to create a mock-up version, made of acrylic panels and an LED module in order to determine the desired lighting effect. A double sided 15W LED fitting was then customised to be seated inside each lantern, producing a soft glow rated as maintenance-free for 20 years with over 100,000 hours at a very low power consumption resulting in reduced energy and costs.
The modules are 3000k, chosen for their ability to produce a warmer light that has a similar ambience and effect to the original heritage lantern.
The LED lights were chosen in part because of their long lifespan, minimising the risk of smashing the fragile glass top domes when changing lights. Two standard 37W Sylvania Street LED streetlights provide roadway illumination in order to address the original issue of ineffective illumination. These are concealed within the light arm structures to reduce glare, while providing drivers with a necessarily compliant level of illumination to ensure road safety. The reduced glare allows the general public to simply focus on the heritage fitting while furthering the photogenic quality of the bridge. The new lanterns will hang off 140 original outreaches, all located in the exact place as when the bridge was constructed.
The lighting project was accomplished efficiently thanks to the array of experts in technical, design and engineering who contributed to the installation. Each heritage fitting weighed 120kg, resulting in structural engineers having to sign off on each outreach. These outreaches had to be checked for rot and decay before the new installations could begin and installation was restricted to times of road closures.
The restoration project on Sydney Harbour Bridge will achieve substantial dollar savings in energy costs alone while ensuring that the RMS can reduce maintenance and servicing costs. In addition, Gerard Lighting has produced a lighting solution that has not only restored the heritage look to the bridge but also meets today’s lighting standards.