Abstract
Building lifetime is a useful metric that serves as an input for many analyses, including property valuation, life-cycle assessment, material flow analysis and building stock analysis. Additionally, building lifetime is essential for the adoption of circular economy principles and retrofitting in construction, which ultimately will help reduce greenhouse gas emissions in the built environment. Yet, limited end-of-life building data and a focus on the design lifetimes of buildings means estimates for actual building lifetimes are outdated, not empirically based or else not compared across regions. By first sourcing and cleaning an extensive dataset of approximately 15,000 demolished buildings, this paper conducts a statistical analysis to: empirically estimate average building lifetimes in nine US and four European cities; analyse trends in building lifetimes across a number of design variables; and understand building obsolescence by applying techniques from survival analysis to buildings. An average lifetime of 71 years was found across all buildings, with a standard deviation (SD) of 28. Significant differences in lifetimes of use types were identified, with residential buildings lasting the longest. Age of the city did not appear to influence the survivorship of demolished buildings, but current and past demolition trends could.
Practice relevance
Buildings are often demolished before the end of their technical lifetime. Building demolition occurs for difficult-to-predict reasons such as economic viability, owner preference and unfavourable architectural characteristics, making actual lifetime hard to estimate. Additionally, sparse data pertaining to demolition have a limited understanding of empirical building age in many US and European cities. In practice, knowing building age is important because it is a metric used in scores of engineering analyses, and it can help in the estimation of the environmental and economic impacts of buildings and cities. This research estimates average building lifetime in nine US and four European cities across building characteristics in order to increase literacy about the demolished building stock, identifying what types of buildings are deemed obsolete.