Demolition of residential buildings in Australia

What it is

Demolition work on a residential site is the dismantling, knocking down or razing of all or part of a building or structure. That captures the full knock-down rebuild of a post-war fibro home, a partial demolition of a back room to make way for an extension, the removal of an old garage to clear the lot and any structural alteration where load-bearing elements come out. Even a partial demolition can release asbestos fibres, drop a wall on a neighbour's fence or destabilise the remaining structure.

In Australia the controls are set by the model WHS Regulations Part 6.5 Demolition work, the model Code of Practice for Demolition Work, AS 2601:2001 The demolition of structures, the asbestos provisions of the model Code of Practice for How to Manage and Control Asbestos in the Workplace, the local council planning approval for the demolition and the state-specific worker licensing rules.

Why residential demolition trips builders up

Most residential builders treat demolition as a procurement decision. Hire the demo contractor, get the slab cleared, start the new build. That works when the demo contractor is competent and the paperwork is in order. The problems start when the builder assumes the contractor has handled everything and never checks the asbestos register, the council notice or the structural support plan.

High-risk construction work classification

Demolition of a load-bearing structure or a structure at least one storey above ground is high-risk construction work under regulation 291 of the model WHS Regulations. That triggers a SWMS requirement before the work starts, a duty to consult with the workers carrying out the work and the principal contractor duties if the project exceeds the cost threshold.

Notice to the regulator

Some demolition work requires advance notice to the state work health and safety regulator. The trigger varies by state. In NSW a notification is required for demolition involving certain structural elements or load-bearing members. In Victoria a Notification of demolition work form is required for certain projects under regulation 5.1.13 of the Occupational Health and Safety Regulations 2017. The lead time is usually five business days. Builders should check the local rule before booking the machine.

Council notice and planning approval

Demolition of a residential building usually requires a development application or a complying development certificate under the planning legislation in each state. In NSW the relevant pathway is often Part 3 of the State Environmental Planning Policy (Exempt and Complying Development Codes). In Victoria a demolition consent under section 29A of the Building Act 1993 may apply. The council notice protects neighbours, heritage values and trees on the lot.

Asbestos register

If the building was constructed before the year 2003 it is presumed to contain asbestos unless tested otherwise. The PCBU with management or control of the workplace must ensure an asbestos register is in place before demolition begins.

What the register must include

The register lists the location, type and condition of identified asbestos containing material across the building. A competent person, often a licensed asbestos assessor, prepares the register from a site inspection and sampling. The register stays with the building until removal is complete and is then handed to the new owner or kept by the demolisher as required.

Licensed removal

Friable asbestos must be removed by a Class A licensed asbestos removalist. Non-friable asbestos exceeding 10 square metres must be removed by a Class B licensed removalist. The licence holder must hold the relevant state authorisation. Builders should sight the licence before the work starts, not afterward.

Structural support and stability

AS 2601 requires that the stability of any structure or part of a structure remaining during or after demolition is maintained throughout the work. On a residential site that often means temporary propping where one room is demolished while the neighbouring room stays, hoarding against the boundary fence where the wall is shared, and an engineer's design where the building shares a party wall with a neighbour.

Adjoining properties

Demolition next to a neighbour's home brings additional duties under the common law right of support and under the state-specific dilapidation rules. Builders should commission a dilapidation report on the adjoining property before the work starts and lodge it with the council. The report protects the builder from later cracking claims that pre-date the work.

TradeLens compliance: who carries the duty

Principal contractor

If the demolition project exceeds the principal contractor cost threshold the PC must hold the WHS Management Plan, the SWMS and the asbestos register before the work starts. The PC cannot delegate the duty by contract.

Demolition PCBU

The demolisher is a PCBU and holds the primary duty for the workers doing the work. The business must hold the demolition licence required by the state, supply the SWMS and apply the controls in AS 2601.

Worker

Workers must follow the SWMS, use the equipment provided and stop work if the structure shows signs of unplanned movement.

Audit triggers SafeWork inspectors look for

Common findings on residential demolition include no SWMS for the load-bearing demolition, an asbestos register prepared after the work started, a Class B removal job done by an unlicensed contractor, no temporary propping for the remaining structure, no demolition notice to the regulator where required and no council approval on file. Each is a stand-alone breach. A prohibition notice is the usual response if a partially demolished structure is at risk of collapse onto a neighbour.

A residential builder can manage the duty chain by sighting the demolition licence, the asbestos register and the council approval before the machine arrives, and by appointing the demolisher in writing as the PCBU controlling that scope. The paperwork takes a morning. The exposure from skipping it can run to six figures and a builder's licence review.