National Library of Australia | Heritage Window Restoration, Canberra

Walter Bunning's National Library opened in 1968 and has been on the Commonwealth Heritage List since 2004. Its facade — bronze-framed windows set between marble-clad columns, with bronze spandrel panels beneath each opening — is the element that most defines how the building is read from the lakeshore.

That created the central constraint. The Library needed the thermal and condensation performance of a modern glazing system, in a building where the frame profiles, sightlines and colour of the original suite are part of what is protected. Nothing could be visibly modernised.

Adapting a 1968 Bronze Suite

ABS Facades developed a custom fabrication methodology inhouse to adapt to the original bronze extrusions. which have no modern equivalent, to accept the Soft Coat Low-E insulating glass units. Frames were removed from the building, assembled and refinished in-house, and treated with an oil patina finish that leaves the metal self-protecting in an external environment and consistent in appearance with the building's original bronze work.

Glass & Glazing details

Cooling Brothers manufactured the insulating glass units at its Perth facility, glazing approximately 500m² of the main facade with InsulCool Ultra Plus 60, a cold weather triple silver soft coat Low-E. Triple silver coatings are specified where a project needs a high level of visible light with a low solar heat gain — at a modelled 58% visible light transmittance against a solar heat gain coefficient of 0.26, the units deliver a light-to-solar-gain ratio of 2.2. For a reading room, that balance matters more than a headline U-value.

Two makeups were manufactured, both with a 4SG warm edge spacer and an argon-filled cavity. Makeup A pairs a 6mm Ultra Plus 60 toughened outer with a 9.52mm clear heat strengthened laminated inner, returning a modelled U-value of 1.295 W/m²·K.

Makeup B pairs an 8mm Ultra Plus 60 toughened outer with an 8mm clear toughened heat soaked inner, at 1.335 W/m²·K. The laminated inner pane provides post-breakage glass retention within the heritage bronze frames.

Digital Printing Unclocks Decorative Match

The front entry bifold doors were beyond repair and required replacement. These original doors were glazed with 60 year old handmade decorative glass that sadly was unable to be reused and required a like-for-like replacement.

After an extensive research and development process that included over 20 different samples, replacement glass was matched using ImagInk digital ceramic printing on 20mm low-iron makeup. Ceramic ink is fired into the glass surface, giving a finish that is permanent and UV-stable. New hardware for the replacement doors was fabricated in cast bronze.