Demolition is a process in which buildings are torn down. Demolition is different from deconstruction, which is carefully taking a building apart to reuse its parts.[1] For small buildings, such as houses, demolition is often simple. Buildings are often pulled down with excavators, bulldozers or small cranes. Other specialized equipment may also be used.[2] Larger buildings may use a wrecking ball swung by a crane.[3] This works well for masonry buildings. Sometimes building implosion is used.[3] This involves using carefully placed explosive charges. If done correctly, the building falls in on itself and not on nearby buildings.
Before a building can be torn down, several things have to happen.[4] A demolition permit has to be obtained from a city, town or county. All hazardous waste must be removed. This includes asbestos, lead paint and any flammable materials.[4] All utilities (water, electricity and natural gas) have to be disconnected.[4] Many municipalities have checklists of what to do before a building can be demolished. They also have checklists of things that must be removed first.