In the pursuit of limiting global warming to 1.5 degrees Celsius, the significance of decarbonizing the built environment cannot be overstated. With nearly 80% of buildings in 2050 already standing today, retrofitting existing structures has emerged as a pivotal lever on the pathway to net zero emissions. Recent findings from a new study underscore both the progress and the pressing need for expedited action in this domain.
The report, Global Retrofit Index Interim Report: Assessing progress on the path to zero, by Kingspan and 3Keel, assessed the ambitions, policies and strides made by significant economies in decarbonizing their built landscapes. While there are encouraging reductions in building emissions across several nations, the trajectory falls short, revealing a plateau in reduction efforts in key EU countries and an alarming 3% increase in greenhouse gas (GHG) emissions from buildings in the United States since 2010.
An American Problem
The findings shed light on the pressing need for significant interventions to reverse this trend and align with the national net zero scenario. The U.S., in particular, faces a daunting challenge: a required 73% additional reduction in building emissions by 2040 to meet net-zero goals. Without decisive action, building emissions are expected to continue their upward trajectory, contradicting the imperative set by the Paris Agreement.
Retrofitting Explained
Retrofitting encompasses a range of techniques and is pivotal in enhancing the efficiency and sustainability of existing structures. Retrofit strategies include adaptive reuse, renovation, extension and restoration, each tailored to address specific challenges.
The benefits of retrofitting are multifold, from improved energy performance and reduced environmental impact to enhanced safety and accessibility. It not only prolongs the lifespan of structures but also contributes significantly to reducing emissions, fostering economic growth, improving building occupant health/wellbeing and promoting social equity.
The Urgency of Retrofitting
While retrofitting solutions exist, significant barriers hinder widespread adoption. These obstacles include insufficient private investment, workforce skill shortages and a lack of awareness among citizens and building owners.
Strategic Retrofits
Strategic building retrofits yield long-term environmental, operational and financial benefits. Understanding the practical implementation involves effective strategies laid out in the below case studies:
Assessing Existing Conditions
MET Atlanta, a century-old warehouse in Atlanta, Georgia, underwent a significant transformation into a multi-use space for entrepreneurs and artisans. As part of the redevelopment, the building owner knew roof renovations, including the aging glass skylights, were crucial to improve building performance. The original skylights had deteriorated over time, leading to leaks and insufficient interior lighting. Prismatic polycarbonate unit skylights replaced the dated skylights, future-proofing the historic building.
Prioritizing Key Improvements
To accommodate more classes and skill labs, Austin Community College in Austin, Texas, acquired the abandoned 92,903-square-meter (1 million-square-foot) Highland Mall. The adaptive reuse project included transforming the “concrete bunker” devoid of natural daylight into an innovative urban educational campus. Perkins&Will and Barnes Gromatzky Kosarek Architects turned the empty spaces from the former shopping plaza into bright learning spaces by using translucent panel skylights.
Additional sustainable efforts include solar panels that offset energy usage and increase energy efficiency, as well as strategic light fixtures that work to reduce light pollution. Additionally, an irrigation system is supported by harvested rainwater and low-flow plumbing fixtures which reduce water consumption by 34%.
Implementing Innovative Technologies
After over 60 years, the Grover Cleveland High School in Los Angeles could no longer hold the expanding student body, forcing a renovation and expansion of the campus. The ambitious plan included seven new buildings and the modernization of current facilities. PBWS Architects implemented a strategic daylighting design, seamlessly integrating translucent walls and skylights with other materials. Product customization in size and shape allowed for a swift and straightforward installation and the flexibility to blend translucent and transparent glazing, providing light control and views of the outdoors.
These insulated daylighting solutions, paired with other sustainability measures such as low-flow water fixtures, stormwater treatment using bioswales and biofiltration planters and cool roofs with a photovoltaic system, assisted the retrofit in becoming Coalition for High Performance Schools (CHPS) verified. This recognition is given to school projects that have integrated the required high-performance features to realize the associated benefits including improved health, productivity and student performance, decreased operating costs, increased energy savings and lower carbon emissions.
A Collaboration for Change
As previously stated, the building industry is retrofitting facilities, but not at a rate needed to meet targets put forth in the Paris Agreement. The question many have is, “How do we expand our understanding and ability to retrofit aging buildings?”
The Global Retrofit Index Interim Report outlines five pivotal elements crucial for effective and scalable retrofitting of national building stocks:
- Setting net zero building performance standards
- Developing a national retrofit plan
- Providing financial incentives and support
- Upskilling the workforce and scaling the supply chain
- Promoting best practices and data transparency
Each of these elements plays a vital role in enabling affordable and large-scale retrofitting. Still, without proactive collaboration from all parties, it is nearly impossible to implement any of them, let alone all five.
In the report, Bianca Wong, Global Head of Sustainability at Kingspan, emphasizes the pivotal role of retrofitting and collaboration, stating, “This analysis again demonstrates the importance of retrofitting as a lever in decarbonizing the built environment…With this report, we encourage policymakers and the construction industry to continue to work together to facilitate change through innovation and regulation to bring forward workable ideas to support retrofit solutions and reduce global building emissions.” This sentiment is echoed by Olwen Smith of 3Keel, who stressed the need to limit global warming and meet the Paris Agreement objectives.
Conclusion and Outlook
To avert the most catastrophic impacts of climate change, decarbonizing the global building stock is imperative. Retrofitting buildings not only reduces emissions but also brings co-benefits, such as enhanced building longevity, improved comfort, health advantages and increased asset value. It’s important to remember that we already have the knowledge, solutions and technologies available to us today to significantly improve energy performance in buildings.
Now, policymakers and the construction industry must continue to work together to facilitate change and accelerate widespread implementation. The challenges are immense, but the time to act is now.
To download a copy of the Global Retrofit Index Interim Report, visit 3Keel.
Note: The Paris Agreement, a legally binding international treaty on climate change, serves as a critical guidepost in our collective efforts to combat climate change.