A House Above the Trees
The Copacabana Cantilever House is a stunning combination of intricate engineering and unique architecture. Designed to appear as if it’s ‘floating’ above the tree line, the house is anything but typical. Arguably one of the most difficult construction sites in Australia, the land included a 60-degree slope with a 6-metre cliff in the center of the site. Although daunting, the creative minds involved looked at this difficult project with excitement, recognizing the site was perfect for a steel cantilever design.
Although the building site provided a creative design opportunity and beautiful views, it also came with access constraints that had to be considered during the design process. Equipment would be limited to a 55T crane and weight restrictions were necessary for processing, transport, and safety. Ease of construction was an important characteristic of the design. Fabricated trusses for the two long sides of the home created the double story structural walls. The built-in platforms around 3 sides of the house negated the need for any scaffolding. Furthermore, the weight and size of the trusses were restricted for galvanizing, transport, site access, and crane capacity. Collaboration between the galvanizer, engineer, builder, and fabricator to ensure all considerations and elements was vital.
The completed build boasts over 55 tons of custom structural steel to achieve the cantilevered structure. To ensure the efficiency and accuracy of installation, multiple trusses for each elevation were preassembled before welding off in the factory. With trusses ranging up to 13 meters in length and over 3 meters in height, the steel required a progressive dip through the galvanizing process. Finally, due to the span of intermediate members, some required cambering and the trusses were pre-set to account for the cantilever once installed.
Hot-dip galvanizing was the obvious solution for corrosion protection in this project. With the ocean just blocks away, the salty air is prevalent in the area creating a corrosive environment. Providing barrier, cathodic, and natural weathering protection, the performance provided by hot-dip galvanizing far exceeds other available options. Galvanizing was also much more likely to survive the tricky installation without damage due to its abrasion resistance. Additionally, in such a difficult area to access, maintenance on a paint coating would be difficult and expensive.
The project was always intended to showcase steel as the primary material. Along with being the key structural element, the hot-dip galvanized steel is exposed to the exterior and interior of the house creating an impressive sight which allows the house to appear like its floating above the tree line. The Copacabana Cantilever House now stands strong above the treetops as an example of utilizing hot-dip galvanized steel to build the house of your dreams.