Demolition involves the systematic and controlled dismantling or destruction of buildings or structures, typically following several steps in a sequence:

Planning and Evaluation: Before any demolition work commences, an in-depth evaluation is undertaken of both the structure and its surroundings. This analysis may include examining its construction materials used and any potential hazards (like asbestos or lead) present within it as well as impactful on nearby structures or utilities. A plan will then be devised that incorporates safety considerations as well as environmental concerns or permits or approvals needed.

Asbestos and hazardous material removal: Before demolition can proceed, any structure containing asbestos, lead-based paint or any other toxic materials must be safely removed and disposed of according to local regulations. Specialized contractors may be hired for this task.

Utilities disconnection: Before commencing demolition work, all utilities such as electricity, gas, water and sewer must be safely disconnected to prevent accidents during the process and protect workers and nearby infrastructure from accidents or damages during dismantling. This step ensures safety both for workers and any nearby infrastructure that might be present.

Structural Weakening: Demolition often begins by weakening the structure. This may require removing non-load bearing walls, windows, doors and fixtures to make demolition more accessible and simpler; occasionally beams or columns may be cut or cut down using appropriate tools and techniques.

Demolition Methods: Differing approaches may be employed when demolishing structures, depending on factors like their size, location and surrounding structures as well as environmental considerations.

Common techniques used include:

Manual demolition: Manual demolition involves using handheld tools, such as sledgehammers, jackhammers and cutting equipment, to dismantle structures piecemeal. This method requires skilled workers and is best used when disassembling smaller structures or in environments where noise, dust or vibration needs to be minimized.

Mechanical demolition: Heavy machinery such as excavators or bulldozers are used for mechanically demolishing structures using attachments such as hydraulic breakers, shears or grappling claws to break apart building components more quickly and efficiently for larger structures. This method provides faster demolition times overall.

Controlled implosion: Under certain circumstances and given enough space and structural conditions, controlled implosion may be used as an effective strategy for building collapse in urban environments. This technique uses explosives strategically placed around a building to cause it to implode inward, thus minimizing risk to nearby structures. Careful planning and expertise must be employed, and typically this strategy is reserved for tall structures located far from other buildings or urban settings.

Waste Management and Recycling: As demolition proceeds, its waste materials must be collected, sorted, and either recycled or disposed of properly to reduce environmental impact and promote sustainability. Salvageable materials like metal, wood or concrete may even be separated for recycling or reuse to further minimize environmental impact while increasing sustainability.

Site Clearance and Restoration: Once the structure has been demolished, any debris left on site must be cleared away by clearing away grading land, backfilling any excavations, and making sure the area is safe and clean. In some instances, post-demolition site restoration activities might include landscaping, erosion control or even prepping the area for new construction.

Notably, the process for demolition can differ depending on factors like location, structure type, regulatory requirements and expertise of the demolition contractor overseeing a particular project.