Dynamic Steel Frames – Manufacturing cold formed steel floor cassette project for Lonsdale Apartments

Scaling New Heights 

Adding eight storeys to an existing 12 storey building from the 70s in the middle of a city brings with it as many challenges as opportunities. Originally planned with timber flooring and joists, the developers soon identified that using these methods would triple the project timeline and push them far beyond their project budget, as each joist would have to be installed one at a time. They started to look at other options, and soon decided on light gauge steel.

“FRAMECAD technology has been a vital part of completing projects and enabling staff to exceed clients’ expectations. No other software can integrate and communicate across other programs. FRAMECAD is the most advanced software/hardware system able to produce fine, detailed, and intricate cold formed steel frames.” -Kate O'Donohue - Dynamic Steel Frame 

 “The client couldn’t reach the same height without using light gauge flooring cassettes,” shares Kate O’Donohue, Marketing Manager for Dynamic Steel Frame. “Access to the site was limited, it increased the speed of installation, and dramatically reduced the labour onsite. CFS floor cassettes were the best option, both for ease of installation and reducing the overall cost.”

Taking a Design-led Approach to Floor Cassettes

Dynamic Steel Frame got to work. With 100s of hours spent detailing and design integration on FRAMECAD Detailer and Tekla, much of the work was done prior to production. The seamless integration of FRAMECAD detailer with Tekla was an essential part of the process as this assimilation sped up the design process and made the detailing work intuitive and straightforward.

 The flooring cassettes consist of the preassembled components that make up the flooring and are craned into position on the build. Each storey of the build consists of 60 cassettes and they are carefully combined together on site. This offsite coordination of joist plumbing, mechanical elements, prefabricated facades, and structural steel was always going to be challenging, so taking this design-led approach was not only vital, but a methodology that provided the project team with confidence and assurance the job would be completed smoothly without error.

 “Using 3D IFC files, we were able to coordinate the different scopes of work to one BIM model, allowing all parties to be on the same path and smooth the integration/work flow on-site,” explains Kate. “The FRAMECAD plug in for Tekla has been invaluable, allowing our detailer to export the frames for the job to the BIM model and meaning discrepancies were minimised.”

 This design-led approach ensured that the design would suit structural steel and allow plumbing and mechanical penetration into the floor from the beginning, eliminating the need for changes during production.

Dynamic Steel’s two F325iT’s (a 75mm profile and an 89mm profile) were used offsite to precisely manufacture 55.2 tonnes of steel into 4,739 square metres of floor cassettes. Each level was constructed in Dynamic Steels manufacturing plant and took their single shift production team a week to roll and assemble each storey before being transported to site by six semi-trucks per floor resulting in 48 trucks across the build.

Lifting lugs were integrated into the cassettes from the beginning and orientation was marked for ease of crane installation, meaning installation could be completed efficiently once on-site by the team in just 3-4 days per level.