Demolition is the dismantling of a building. Demolition is a complicated process that requires proper planning in order to ensure the safety of workers, bystanders and adjacent buildings. It involves the following things:

1. Obtaining city council approval

Local government approval is a necessity before you can demolish any building in Australia. There are two types of licenses: a demolition license and a restricted demolition license. A demolition license is for demolitions that include buildings over 15 metres in height, involve the use of explosives and tower cranes and may have chemical installations on site. A restricted demolition license is required when using mechanical demolition and the building is not more than 15 metres in height.

2. Building survey

This involves the survey of the building and its surroundings. Before a building can be demolished, there are factors to consider such as the location of the building, building materials, reason for demolition and how to dispose of the debris. The presence of hazardous waste on site and drainage conditions of the property are also surveyed. This process also involves a structural survey of the building. A structural survey looks at the method of building, structural integrity of any underground basements and the current condition of the building. There is also an investigation of whether the building may contain asbestos, especially if it was built before the asbestos ban.

3. Risk assessment

There are many risks involved in the demolition process such as falling objects or unplanned collapse. This stage involves minimising risks involved with demolition before the process can begin. It involves fencing the perimeter around the building, putting up warning signs for passersby and providing workers with protective clothing. Workers, site supervisors and engineers also require a briefing of the potential risks of demolition. Any hazardous materials that are flammable should be removed from the site or stored properly.

4. Choosing a demolition technique

There are two main methods of demolition:

1. Implosion. This is the use of explosives placed strategically around support structures of the building such as beams. It is very fast and causes the building to collapse on itself. It is a dangerous method because flying debris may injure onlookers, and it is associated with high pressure that may damage adjacent buildings.
2. Mechanical demolition. This involves the use of machines such as wrecking balls, excavators and sledgehammers. Sledgehammers are typically used for small structures; wrecking balls are popular for concrete structures and excavators are used for demolition and moving debris into trucks.

Contact demolition companies like Roach Demolition & Excavations for more information.