In the heart of the construction industry, a groundbreaking study has emerged, shedding light on the often-overlooked metric of building lifetimes. Led by Juliana Berglund-Brown from the Massachusetts Institute of Technology, this research delves into the lifespans of demolished buildings across nine US and four European cities, offering insights that could reshape how we approach building design, demolition, and sustainability.
The study, published in the journal ‘Buildings & Cities’ (translated as ‘Gebäude & Städte’), sourced and cleaned an extensive dataset of approximately 15,000 demolished buildings. This data trove was then subjected to rigorous statistical analysis to estimate average building lifetimes and understand the factors influencing building obsolescence.
“Building lifetime is a crucial metric that serves as an input for many analyses, including property valuation, life-cycle assessment, and building stock analysis,” Berglund-Brown explains. The research found that buildings have an average lifetime of 71 years, with a standard deviation of 28 years. However, significant differences were identified across various use types, with residential buildings lasting the longest.
The study also revealed that the age of the city did not appear to influence the survivorship of demolished buildings, but current and past demolition trends did. This finding challenges conventional wisdom and opens up new avenues for understanding urban development and decay.
For the energy sector, the implications are profound. Buildings are often demolished before the end of their technical lifetime, a phenomenon that has significant economic and environmental impacts. “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,” Berglund-Brown notes.
The research highlights the need for better data collection and analysis of building lifetimes. It also underscores the importance of adopting circular economy principles and retrofitting in construction to reduce greenhouse gas emissions in the built environment.
As the construction industry grapples with the challenges of sustainability and urbanization, this study provides a timely and valuable contribution. It offers a data-driven approach to understanding building lifetimes, which can inform policy decisions, improve building design, and enhance the longevity of our urban landscapes.
In the words of Berglund-Brown, “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.” This increased literacy could be the key to unlocking a more sustainable and resilient built environment.
As we look to the future, this research shapes how we might approach building design and demolition. It challenges us to think critically about the lifespan of our structures and the impact they have on our cities and our planet. In doing so, it paves the way for a more informed and sustainable approach to construction and urban development.