The design of the Fitzgibbon Community Centre by Richard Kirk Architect was created in response to the common suburban landscape where it is located. The materials used on the project enhance and reflect this aim. This includes the sculptural blades of Xlerplate weathering steel, which is a material that responds to the corroded car bodies once found on site.
A hot-rolled structural weather resistant steel, the Xlerplate weathering steel from Bluescope Steel has a nominal minimum yield strength of 350 MPa, good formability and weldability.
While typically used for truck bodies, shipping containers and rolling stock, weather resistant steels have also been used for architectural applications given its gradual improvement and evolution. In the Fitzgibbon Community Centre project, it is used as cladding.
“People like to use the weathering steel because of its natural, rustic look, and the fact that it tends to blend into the natural environment,” says Bluescope's technical manager, John Dryden.
“It goes really well with gardens or rock features, or even combined with other natural building products, such as timber.”
The beautiful patina of age of the weathering steel is attributed to the way the material works, as well as the particular chemical composition of the steel, which consists of alloys such as copper, chrome, phosphorous and nickel.
As the steel is exposed to the right weather conditions, it develops a complex protective oxide layer on the steel surface. It is this oxide that gives the steel its appearance, as well as its corrosion-resistance.
In the right conditions, away from heavy industrial environments or salt spray, the weathering steel exhibits up to approximately four to six times greater resistance to corrosion than normal structural steel sheets. However, this layer of protective oxide is reliant on a bold exposure to the atmosphere of all the steel surfaces, alternate wetting and drying of all the steel surfaces, and a limited access to atmospheric chloride contamination.
According to Dryden, a challenge that could occur with the application of the weathering steel is that as the material develops, the oxide layer will run off and stain the surrounding area. Design therefore plays an important role when accommodating for the possible run off.
“Whoever worked on the Fitzgibbon project seems to have done a good job,” says Dryden, explaining that the panels of the building were constructed and run into garden beds.
“Any run offs from the cladding therefore won’t stain the surrounding area, but will just wash off into the garden.”
Another design concern raised is the welding of the weathering steels to other weathering steel plates or plain carbon steels. Over time, the standard weld metal is expected to discolour and corrode at a different rate to the weather resistant steel. This means that for some projects, the need to colour match will require special electrodes to be used.
However, Dryden points out that normal tools or low hydrogen electrodes sufficed in the Fitzgibbon project because the weathering steel was only used as a cladding material.
Fringed by the weathering steel, the Fitzgibbon Community Centre redefines the building’s relationship to the landscape as a piece of artwork within the environment. The durability and integrity of the materials used adds value to the building, which is set to age beautifully over time.
Images: Scott Burrows
