Building life cycle refers to the view of a building

Building

In architecture, construction, engineering, real estate development and technology the word building may refer to one of the following:...

 over the course of its entire life - in other words, viewing it not just as an operational building, but also taking into account the design

Design

Design as a noun informally refers to a plan or convention for the construction of an object or a system while “to design” refers to making this plan...

, installation, commissioning, operation and decommissioning phases. It is useful to use this view when attempting to improve an operational feature of a building that is related to how a building was designed. For example, overall energy conservation

Efficient energy use

Efficient energy use, sometimes simply called energy efficiency, is the goal of efforts to reduce the amount of energy required to provide products and services. For example, insulating a home allows a building to use less heating and cooling energy to achieve and maintain a comfortable temperature...

. In the vast majority of cases there is less than sufficient effort put into designing a building to be energy efficient and hence large inefficiencies are incurred in the operational phase. Current research is ongoing in exploring methods of incorporating a whole life cycle view of buildings, rather than just focusing on the operational phase as is the current situation.