Without giving it much thought, you’d likely assume that constructing a building takes much more planning and effort than demolishing a building. You’d be surprised, however, to learn about the engineering expertise required to safely and effectively demolish a building. Below are four methods of demolishing buildings a few stories tall and massive skyscrapers. Prepare to have your mind blown.

Implosion

It’s fascinating to watch a skyscraper crumble in on itself during a demolition. For the outsider, the process of preparation is a mystery but the explosion and its dramatic result is intriguing. 

Explosive demolition, or implosion, “is a highly specialized part of the demolition process requiring an in-depth knowledge of the nature of structures and the use of explosives,” according to the National Demolition Association. For larger structures, explosive demolition is a safe and efficient method. 

In an implosion, explosives are placed in strategic areas to remove the support structure. This causes the section above the area to fall down on the lower part. It’s important to note that it is gravity that brings the structure down — not the explosives. Some implosions cause the building to collapse down into its own footprint, while other implosions may bring the building down over one side.

High Reach Arm

In a high reach demolition, excavators with super long boom arms use specialized hydraulic attachments to access tall structures 20 stories or more. The building is broken up from the top down. The machine removes large chunks of the structure, while the crew on the ground breaks the pieces down and prepares them for disposal.

This type of demolition is commonly used on structures made with concrete, masonry, steel and mixed-material structures.

Wrecking Ball

In a wrecking ball demolition, crane operators use a wrecking ball that can weigh up to 13,500 pounds to crush a building with repeated blows. The wrecking ball is either dropped onto or swung into the building. As you might expect, a wrecking ball demolition is very loud and dusty and creates a lot of vibration.

Selective Demolition

This method is also known as strip-out demolition and is preferred choice for builders interested in reusing and recycling building materials. Materials like wood, brick, metals and concrete can be recycled for future use. The downside of this method is the time and labor required to strip the building.