Post-Tensioning Excellence for Student Accommodation

Located in the heart of Kensington, Sydney, Scape Lachlan is a landmark new development designed to meet the growing demand for high-quality student accommodation. Positioned at a major junction along the Anzac Parade corridor — part of ‘Todman Square’ and immediately adjacent to the Todman Avenue light rail stop — the project is ideally placed to serve students from nearby institutions such as UNSW, NIDA, and TAFE Kensington.

Designed by PLUS Architects, Infinity Constructions was commissioned to complete the project for Scape Australia.

Scape Lachlan celebrates the existing character of Kensington by retaining the heritage façade and introducing a striking new 19-storey corner tower. This tower envisioned as a “floating” form with a distinctive peeling veil façade, acts as an urban marker at the prominent intersection. Flanking this tower are lower-built forms of 10 and 13-storeys that reinforce the street wall character and contribute to a cohesive urban streetscape.

At ground level, the project offers a dynamic mixed-use plane featuring retail spaces, a supermarket, a community innovation hub, and active lobbies. A connecting through-site link and internal plaza further activate the precinct, enhancing connectivity and community engagement.

On the upper levels, Scape Lachlan provides an impressive 693 student accommodation and co-living beds, creating a vibrant vertical community for Sydney’s growing student population.

Interspan’s post-tensioning for the PSA Tower

Interspan played a pivotal role in the delivery of the 20-storey PSA Tower — the signature vertical element of Scape Lachlan. Engaged for the post-tensioning works, Interspan delivered solutions across 23,423 m² of slab area, ensuring efficient construction and long-term performance.

Key achievements on this project included:

• Achieving tight timelines, supporting an accelerated construction program.

• Close site-based coordination, particularly critical on the complex ground floor transfer slab.

• Successfully navigating a tight site footprint, with typical levels just over 550 m², requiring precise planning and execution.

Working in collaboration with consulting engineers EI Australia and PLUS Architects, Interspan provided a tailored post-tensioning approach that addressed the project’s architectural ambitions and challenging structural requirements, including seamless integration with the heritage façade.

Engineering Innovations for Performance and Flexibility

A major innovation on the PSA Tower was the use of Surelok Temporary Moving Joints (TMJs) and grouted dowel bars to manage tensile forces resulting from drying shrinkage.

The Sureloks allowed controlled movement in two horizontal directions before locking, ensuring permanent structural stability and integrity. Additionally, the use of the 200S meant that propping could be removed prior to grouting, further streamlining the site program.

Grouted dowel bars further enhanced slab continuity and strength, providing long-term durability across critical areas of the structure.

Heritage Integration and Design Excellence

A defining feature of Scape Lachlan is its preservation and celebration of the existing heritage façade. Interspan’s innovative engineering enabled the new PSA Tower to seamlessly integrate with these heritage elements, showcasing technical expertise and commitment to architectural integrity.

Interspan is proud to have delivered the post-tensioning works on the PSA Tower at Scape Lachlan — a project that not only expands Sydney’s student accommodation capacity but also sets a new benchmark in structural innovation and urban design.

Image Credit: Plus Architecture