You can define demolition as destroying, wrecking, dismantling, or razing any building or structure in a controlled manner. It seems relatively straightforward, and we have plenty of demolition experts in NZ, but that doesn’t mean all demolition projects are handled in the same way.

In fact, the type of demolition methods experts use can depend on the building’s size, design, location, and many other factors. Out of curiosity or to plan your next demolition project, it might help to be aware of the different types of demolition methods, many of which are mentioned below.

 

Manual Demolition

Manual demolition is an option many demolition teams consider in narrow and localised areas. Typically, this form of demolition requires hand tools like picks, sledgehammers, and jackhammers, all of which need a significant amount of human energy.

However, this method might typically be preferred when building companies and owners want to recycle materials or undertake careful demolition of specific areas.

It’s worth noting that it’s among the most time and labour-intensive demolition methods while also requiring many more protective measures than others. There’s a genuine risk of flying debris, and demolition teams must ensure the site is well-fenced and sign-posted for their safety.

More often than not, demo teams performing manual demolition will work floor by floor in a downward sequence.

 

Mechanical Demolition

Mechanical demolition is undoubtedly the most preferred option for demolition workers. It involves the use of heavy machinery, such as cranes, excavators, bulldozers, and even wrecking balls. These are required to pull or push a building down and clear the resulting debris from the site.

Cranes are desirable for high-level demolition as they can be linked to wrecking balls that swing into the sides of buildings and bring them down. Most cranes are also equipped with wire ropes, chains, sheaves, and hoists to lift and lower materials.

Demolition workers might also rely on cherry pickers to access tall buildings, demolition excavators with specialised cabs and booms, and crawler loaders to move materials and dirt. Workers tasked with small demolition projects might also bring backhoe loaders to their worksite, which have digging mechanisms similar to excavators.

 

Controlled/Induced Collapse + Explosives

A controlled or induced collapse refers to the systematic removal of key structures within a building to bring it to the ground. Typically, controlled collapse is only used on detached structures with minimal risk of damage to surrounding buildings. With this method, a range of tools is used, such as chains, slings, and wired ropes. You also, of course, sometimes need explosives.

Only competent specialists can use explosives, especially in heavily populated areas. Experts understand the strategic placement of explosives that can allow the building to come down at an appropriate (and safe!) angle.

 

Hydraulic Crusher

Many demolition businesses use a hydraulic crusher to bring a building down. This involves breaking away a concrete structure with a machine-mounted hydraulic crusher. It provides excellent mobility, is suitable for a broad range of building types, and allows operators to separate steel bars from their frames.

Typically, this demolition method takes place floor by floor and requires a range of precautionary measures and adequate floor support for the machine.

 

Chemical Demolition

We have some incredible technology at our disposal, so we may as well make full use of it! Chemical demolition is one of the more exciting advancements in recent years, which involves the use of a non-explosive chemical demolition agent with thousands of PSI of expansive strength upon being combined with water.

Demolition experts would drill holes into a structure and pour the chemical agent into those holes. When water is added, it starts silently fracturing the concrete until it’s broken down into manageable-sized pieces.

While traditional demolition work is noisy, dusty, invasive, and disruptive, chemical demolition isn’t in comparison. It can also be much more affordable than many other common demolition methods we rely on.

 

Selective and Strip-Out Demolition

Some clients contact demolition companies asking for only a portion of their building to be demolished. They might have a large building that’s mostly in excellent condition, with only a small interior part that isn’t.

In that case, they might ask for specific parts of a building, such as the interior, to be removed while the exterior and remaining portions are to be kept in place. This can require the use of sledgehammers on the inside and skid steer loaders, excavators, and bulldozers, for the exterior.

Alternatively, someone might request a strip-out demolition involving dismantling a structure for recycling, refurbishment, or reuse. In this situation, a significant amount of manual demolition work can be required.

 

Get Ready For Your Next Demolition

Every demolition project is different, which means a range of demolition methods can be required to suit each project. If you’re considering demolishing a building to undertake a new project, now might be the right time to contact the experts and discover the best demolition method for your needs.