44 Martin Place
Solutions for complex heritage refurbishment in busy CBD location
The refurbishment of 44 Martin Place transformed the State Heritage listed building into a contemporary, connected workplace tower, whilst restoring the 1930s exterior to its former glory.
Significant architectural additions included a structural atrium penetration across 13 floors to accommodate an interconnecting staircase, and a new ‘floating’ pavilion and garden terrace on the rooftop that adds two new floors of commercial office space.
The full refurbishment works also included: services infrastructure upgrade, structural strengthening, base building makegood, lobby upgrade, end of trip facilities and heritage façade refurbishment.
During the Early Contractor Involvement phase, the team’s design work, investigation and preplanning helped to de-risk the project by resolving structural and strengthening requirements.
The team used proactive safety and planning to manage the works in a busy CBD location, as well as maintain safety and continuity during the pandemic.
Design and delivery solutions
Heritage: Key heritage elements included original doors, window and lift reveals, and granite entry portal. To match the original materials the prototyping and testing process was informed by specialist restoration techniques and subcontractors. A suitable stone quarry was sourced to match the existing heritage façade sandstone.
Structural strengthening: The structure required strengthening to achieve the Building Code and methodologies that would enable it to handle impactful works. New structural steel and concrete elements were rebuilt around the atrium penetration and a cross laminated timber slab structure was selected for the new top floors to reduce the load.
The columns and cores were strengthened to achieve the latest fire and earthquake standards and the new structural steel grillage also allowed for the load of the tower crane. A benchmark floor was established using propping that enabled the team to assess strengthening requirements, providing more certainty for the program, cost and quality.
Methodologies and access: Site establishment required consideration of the building’s heritage constraints and access. To protect the building, an internal hoist was used which required floor penetrations to non-heritage areas. A tower crane enabled safe delivery of materials to multiple locations. The 10 storey feature staircase was fabricated off site, with balustrades already installed for added safety. Over a week, each staircase was then craned in through the roof.
Live environment: Methods were developed to protect the operations of the luxury retail tenants on the ground floor, including acoustic hoarding, after hours impactful works and use of the tower crane. Other safety measures included scaffold grillage and catch decks to allow ground floor works to continue during the atrium build.