Project: Concrete Balcony Cut-Out – Catch Deck Propping
Location: Narrabeen, NSW
Sector: Residential Remediation
Client: Fluid Building Services
Services Provided: Temporary works design, catch deck installation, back propping
Equipment Used: Titan Props, scaffold tube bracing, LVL beams, Formply sheeting
Project Overview
Legend Hire engineered and installed a custom catch deck propping system to enable safe concrete balcony cut-out works on a residential remediation project in Narrabeen, NSW. The client, Fluid Building Services, required a temporary structural support solution that could safely capture material during demolition while managing vertical loads across a suspended slab. Access constraints required all equipment to be manoeuvred through an existing scaffold, and the suspended slab configuration necessitated back propping to distribute loads safely to the structure below. Legend Hire designed and installed the catch deck using Titan Props, scaffold tube bracing, LVL beams and Formply sheeting.
The Challenge
The remediation works required a section of an existing concrete balcony to be cut out. To do this safely, a catch deck was required beneath the work zone to contain debris and provide edge support during the cut-out process.
Two site-specific constraints added complexity to the design. First, access to the work area was restricted to the existing perimeter scaffold, meaning all equipment had to be rigged through the scaffold frame and positioned without direct ground access. Second, the catch deck was required to bear load on a suspended concrete slab, which meant the vertical loads introduced by the propping system could not be transferred directly to grade, back propping was required to safely distribute those loads to the structure below.
The Solution
Legend Hire engineered a custom catch deck configuration using Titan Props as the primary vertical support members, connected with scaffold tube bracing to provide lateral stability across the assembly. LVL (Laminated Veneer Lumber) bearers were installed across the prop heads to provide the structural deck framing, with Formply sheeting laid on top to form the catch surface.
The entire system was designed to be assembled within the scaffold access constraints, with components sized and sequenced to allow installation through the existing scaffold bay dimensions. Back propping was incorporated into the design to transfer imposed loads from the suspended slab through to the supporting structure below, preventing overstress of the balcony slab during the cut-out works.
Equipment Used
- Titan Props: primary vertical load-bearing support members; adjustable to suit slab-to-slab height
- Scaffold tube bracing: lateral restraint across the propping array
- LVL (Laminated Veneer Lumber) beams: structural bearers spanning between prop heads
- Formply sheeting: deck surface providing a solid catch plane beneath the cut-out zone
The Outcome
The catch deck was successfully installed within the scaffold access constraints, providing the structural platform required for Fluid Building Services to proceed with the balcony cut-out works safely. The back propping configuration ensured suspended slab loads were managed appropriately throughout the works. Demolition proceeded without incident, and the temporary propping system was removed on completion of the cut-out works without structural impact to the remaining balcony or building structure.