A product life cycle is an assessment of resource consumption, performance, and environmental impacts at each phase of an industrial product’s life. It consists of the extraction of raw materials, the processing of those materials, manufacturing, shipping, use, maintenance, and finally disposal or recycling. Life cycle assessment is based on information derived through the product life cycle.
In order to create a product, the first stage in its life cycle is the extraction of raw materials from the earth. These materials must be processed, transformed, or combined to create materials that serve as the building blocks of a product, such as metals or plastics. The processed materials are then combined with other materials to manufacture the final product, which is packaged and shipped to retailers or warehouses to be sold. The product use phase begins at the time of purchase and ends at its disposal. This includes any additional energy or resources needed to use or maintain it. Disposal may mean that a product ends up in a landfill, or that it is recycled, reused, or recovered.
Some product life cycles only contemplate phases of production, rather than a product’s distribution and use. These truncated life cycles are referred to as “cradle to gate,” in reference to the gate of the factory. Other cycles consider production through landfill disposal. However, a more sustainability-oriented product life cycle terminology is referred to as “cradle to cradle,” which encourages alternatives to the landfill such as recycling or reuse.1
The product life cycle of buildings has a slightly different specification. It begins with materials manufacturing, then continues to construction, use and maintenance, and finally end of life. Materials manufacturing consists of the extraction and transportation of raw materials, the fabrication of finished or intermediate materials and building products, and finally their packaging and distribution. This is followed by construction and use and maintenance – the building’s regular consumption of energy and water, its waste output, repairs and replacements, and the transport and equipment needed to carry out those repairs. The final stage of a building’s life examines the waste produced and energy consumed in demolition and transportation of waste materials. This may include recycling or reuse of waste materials. Analyzing a building’s life cycle can provide information about its environmental footprint—its contribution to global warming, destruction of habitats, use of resources, and harmful emissions.2