Theatre Royal Sydney

The history of the Theatre Royal in Sydney stretches back to the early 1800s, making it one of Sydney's oldest theatrical institutions. It is also an important architectural landmark - the current theatre was designed by acclaimed achitect Harry Seidler in 1976, along with the adjoining MLC Centre. 

In 2016, extensive renovations were carried out to the Theatre Royal and the MLC Centre (now known as 25 Martin Place). The careful restoration of the heritage-listed theatre took the opportunity to upgrade the facilities to meet updated compliance requirements, better meet the expectations of patrons, and accommodate modern production specifications. Northrop was engaged as the structural engineers for the project, working alongside Trafalgar Entertainment, Scott Carver and Buildcorp. 

One part of the work involved adding a new section to the end of the existing cantilevered seating to provide an additional row of seats. This required evaluation of the existing post-tensioned concrete structure to ensure it could support the additional load, as well as a progressive deflection analysis to determine the impact on audience sight lines. With the base-build renovations adding a new floor above the theater, the capacity of the existing 2-meter deep steel beams and supporting concrete transfer beams needed to be assessed. This information was then used to establish the usable load limitations for the theatre. 

Our team worked very closely with the project architects, Scott Carver, to preserve important features from the original Harry Seidler design, while significantly upgrading the seating, operational areas, and services. 

Reopening of the iconic 1,200 seat theatre aims to put Sydney on the map to host new productions and compete on the world-stage for international tours. Restoration of this cultural icon has been a once-in-a-lifetime experience for the project team. 

To learn more about this project, contact Lilian Lee - Principal | Structural Engineer ( or Braeden Perrott ( on 02 9241 4188.  

Client Name
Trafalgar Entertainment/ Buildcorp
Construction Value
$12 million

Want to keep in touch? Sign up