Complex Structural Demolition – Elizabeth Bay

Perfect Contracting was contracted for a large-scale, complex structural demolition of a 4-storey building in Elizabeth Bay by Novati Constructions. The building consisted of brick walls, 200 mm thick concrete floor and roof slabs and up to 450mm thick ground floor slab.

The scope of work involved in early planning and enabling works included:

• obtaining council permits
• site and risk assessment
• structural assessment of the Demolition Management Plan
• removal of hazardous materials
• installation of safety precautions and establishing exclusion zones and;
• installation of environmental protection and controls

Construction scope included:

• Internal strip-out of fixtures including all paving and tiling within the building and outside.
• Installation of more than 1200 structural props over a total of 4 levels of the complex.
• Management of the design, procurement, & installation of earthquake bracing.
• Demolition of walls, slabs, columns, footings and lift shaft whilst working on suspended slabs.
• A total of 3000t of rubble was disposed of by creating drop zones on all levels within the building.
• Over 1000 square metres of concrete scabbling.
• Over 500 lineal metres of concrete cutting using a wall-saw and was completed by the Perfect Concrete Care team.

This was an exceptionally complex project and therefore, presented several significant challenges. The key challenges included environmental factors i.e., sensitive receptors, procurement of long lead items i.e., structural steel, maintaining safety & structural integrity during demolition and, restricted access. Due to the building’s placement in a residential neighbourhood, the project also posed challenges regarding limited street access, noise, and vibration.

Perfect Contracting overcame the challenges through engineering unique methodologies, diligent planning, and management.  Our skilled team of experts maintained robust quality assurance procedures to identify and rectify issues early on. We consistently maintained effective communication with project team, client, and stakeholders. Perfect employed third party structural assessment and certification of Demolition Management Plan which was continuously updated throughout the project lifecycle to
incorporate any changes and latent site conditions.

Throughout the construction phase, Perfect maintained high safety standards through the use of weekly checklists that were completed by the Site Supervisor and ensured that all signage was maintained and manoeuvred to suit the changing footprint of construction works. Perfect also installed edge protection fencing, Perfect Contracting employed a top-down demolition methodology, resulting in works beginning with the roof and progressively working down through all levels until the basement was reached. This was achieved through the utilisation of small excavators and Brokks, with manual demolition employed where necessary. A mobile gantry was used for transporting small machines to the required levels. Detailing of the concrete slabs was achieved through the use of several concrete cutting methods which allowed Perfect to achieve smooth and accurate finishes in line with survey requirements.

Designated drop zones and experienced operators were paramount in achieving efficient and timely loadout of demolished material whilst maintaining the structural integrity of the complex. In the end, solely the roof and five raised slabs on supports were left intact. Compliance was achieved through the use of vibration and noise monitoring as well as working under specific DA conditions, such as utilising respite periods during the demolition process, installation of scaffolding containment mesh as a secondary dust barrier.

Compliance was achieved through the use of vibration and noise monitoring as well as working under specific DA conditions, such as utilising respite periods during the demolition process, installation of scaffolding containment mesh as a secondary dust barrier.

Perfect Contracting employed an engineered solution that included the use of water cannons, sprinklers, and built-in machine dust suppression systems to combat and control silica dust within the work environment.

Perfect Contracting efficiently delivered the challenging project within the allocated budget. Despite the complexity of the project, our dedicated team worked relentlessly and managed to successfully complete the project within 12 months. No incidents or LTIs were incurred throughout the duration of the project. Demolition was carried out carefully to minimise disruption to neighbouring properties. All Perfect personnel performed exceptionally with clear lines of communication and understanding of each role and the associated delegations which allowed for increased productivity. Our client, Novati Constructions, commended us on the smooth delivery of such a complex project and was greatly satisfied with the quality of our work.