As extreme weather events become more frequent, buildings will need to be designed for greater durability, a new study by Drexel University has suggested.
According to the study, Resilience in building life cycle assessment: a critical review and framework for time-integrated functionality, current life-cycle assessments (LCAs) of buildings may be insufficient, as they often don’t account for damage, disruption and restoration costs linked to extreme weather.
‘Changing the calculus’
“If we truly want to reduce the environmental impact of building construction and operation, which currently accounts for more than a third of global greenhouse gas emissions, it is vital that we look at the full picture,” commented Fernanda Cruz Rios, PhD, an assistant professor in the Howley College’s School of Engineering, who conducted the research.
“More frequent extreme weather events are changing the calculus around what it takes to maintain a functional building – this must be factored in when thinking about resource consumption.”
Systemic review
Cruz Rios undertook a systemic review of 40 studies looking at building resiliency through the lens of life cycle assessment, across four main categories: seismic activity, heat, flooding and wind.
As the study found, under existing approaches, two buildings with different levels of resilience could receive similar environmental assessments when they are first constructed. However, if one building is severely damaged during a storm and remains unusable for months, the emissions and resource consumption associated with temporary services, repairs and rebuilding may not be reflected in its original assessment.
“Under current life cycle assessment methods, two hospitals – one designed to keep functioning through a disaster and one that isn’t – can end up with nearly identical environmental scores on day one,” Cruz Rios added.
“But if one goes dark for months after a storm and has to be rebuilt, while the other keeps running, that difference never shows up in how we measure their environmental impact. Being able to design for that resilience, and actually measure what it’s worth, is what’s missing right now.”
The study proposes a framework that considers the environmental costs of measures such as stronger construction materials, redundant building systems and backup generators, as well as the compensatory services required while a building is out of operation.
Complementing existing practices
According to Cruz Rios, the framework is intended to complement existing LCA practices rather than replace them, and could, in time, be incorporated into environmental systems such as LEED, the National Green Building Standard and Green Globes.
“This isn’t a new system that replaces what designers already do,” Cruz Rios said. “It’s a set of modules that plug directly into the life cycle analyses they’re already running when a building is designed. Adoption into formal standards will likely take time – that kind of change always does – but I’m already hearing from designers who’ve noticed this gap on their own and want a way to prove that building for durability is also building sustainably. Right now, the tools don’t give them that.” Read more here.
