Project Overview

Winner of the City of Sydney Design Excellence Competition in 2013, Arc represents an architectural statement that combines craftsmanship and texture to create a contemporary tower that respects the historical context of its surrounding urban fabric.

A pair of 26 storey towers with a distinctively arched roofscape becomes the latest mixed-use building to join Sydney’s celebrated skyline. The 300,000 handcrafted bricks blend seamlessly within the adjacent heritage buildings. Materials and details of Arc have a level of intricacy and authenticity that enrich the delicate historic context.

Project Commissioner

Crown Group

Project Creator

Koichi Takada Architects

Project Brief

Koichi Takada Architect’s design for Arc focuses on providing a building that both enhances the existing streetscape and provides an iconic and recognisable addition to Sydney’s skyline.

The design concept of Arc relates to the historical context of the site. We carefully studied the proportions of the arches and materiality used historically in Sydney. The design has a heavy masonry character at the base, whereas the tower above has finer, lighter materiality.

Inspired by the masonry component in the significant heritage buildings next door, and drawing from their characteristic arches, a duality is introduced to the façade and represented by the varied aesthetics of the podium and tower. The through-site link comprises an 8-storey atrium and is designed to enrich and regenerate public amenity in this area of the CBD. The sculptural tower element floats above the podium, shaping the skyline with a gentle and organic form.

Arc organises 221 apartments; 86 serviced apartments and 135 residential apartments. Included in the design is a retail precinct below an 8-storey high public through site link, reactivating the historic Skittle Lane. The residents, both temporary and permanent, enjoy impressive amenities on the rooftop areas and have the opportunity for casual interaction with their neighbours.

Project Innovation/Need

Arc has two distinct parts with contrasting material aesthetics. Both the heritage-inspired base and architectural tower use the ‘arch’ motif to work together to create an integrated aesthetic. The duality of the design is what makes this building unique and special.

The roof feature of Arc celebrates the outdoor lifestyle that Sydney is famous for, and the first high-rise residential design to break the mould. An organic crown feature instantly distinguishes Arc from the surrounding context, a curved roof form that celebrates how the tower meets the sky. The rooftop opens up a new dialogue with what is possible in our future cities activating not only the ground plane but also the sky-plane. When you come up to the rooftop, you can see the Sydney Harbour as a backdrop to the city view. The curved arches connect you with the organic and undulating lines of Sydney Harbour and its best natural assets.

With an iconic and unique design, the building responds to the City of Sydney’s 2030 Vision, contributing to the CBD skyline and ensuring Sydney maintains a global city. The building also responds to the increasing demand for apartment living. The hotel component will add further short-term accommodation to an undersupplied CBD, boosting tourism. The retail component will attract high-end tenants that will re-gentrify the immediate surrounds and improve local economic activity.

Design Challenge

The building façade involves a level of intricate masonry work, which has been a challenging part of the design details. In studying the quality and aesthetic of the surrounding heritage buildings, it is clear that the type of masonry work and bricklaying, so common in our heritage buildings, is somewhat of a lost art. The façade engineers and construction team provide invaluable knowledge about how to deliver a traditional façade in a modern setting. The tower has not been without challenges, with the feature roof arches crossing over from structural arches to window frames. Seen from afar, as part of the city skyline, as well as up-close in an apartment balcony, meant integration of disciplines was key to the success at both scales.

Sustainability

Arc is designed to satisfy energy and efficiency performance standards. A BASIX assessment has been prepared and the development has been designed to achieve verification for water conservation, thermal comfort and energy efficiency. The insulation value for the walls, roofs and floors combined with window dimensions, locations, glass types and shading devices has achieved compliant heating and cooling loads.

Natural ventilation has been maximised throughout the entire building to reduce reliance on mechanical ventilation systems. Over 75% of the apartments are naturally cross ventilated. The through-site link furthers this with the provision for natural light and ventilation, while the atrium facilitates cross ventilation in apartments that would otherwise only have a single aspect for openings. The design allows for ceiling ventilation spaces to cross common corridors. Facilities for rainwater collection and re-use for irrigation.

The layout of the residential levels has maximised the available solar access. Being an east-west facing site in an urban setting, constraints exist for providing adequate light to the podium. The surrounding buildings completely overshadow the Kent Street podium facades in the afternoon, and even the Clarence Street façade is restricted to receiving light before 10 am. The internal layout has been designed to place the living rooms to the building periphery, with balconies placed in front of the bedrooms. The facade expression is designed with angled walls to capture even the slightest angle of the sun. This allows the living space as much access to the external glazing line as possible.