A holistic approach to adaptive reuse: systems thinking to sustainable transformation

The topic was presented at the recent 2025 International Green Building Conference in Singapore in July. It is promising to see the understanding and willingness to collaborate to turn complex challenges into opportunities to create a more decarbonised built environment.

Beyond embodied and operational carbon

Traditionally, sustainability in buildings has focused on operational carbon—emissions from energy use during occupancy. However, embodied carbon, which includes emissions from material extraction, manufacturing, and construction, is now recognised as equally critical. According to the UN Environment Global Status Report, the built environment contributes 39% of global carbon emissions, with embodied carbon accounting for nearly 45% of emissions from new construction between 2020 and 2050.

Adaptive reuse addresses both dimensions. By retaining structural elements, it avoids the carbon-intensive processes of demolition and new construction. Retrofitting with energy-efficient systems and passive design strategies—such as natural ventilation, daylighting, and renewable energy integration—further reduces operational emissions. This dual benefit positions adaptive reuse as a cornerstone of sustainable urban development.

A systems-thinking design approach

Adaptive reuse demands more than technical upgrades—it requires a holistic, systems-thinking mindset. This means aligning the goals of architects, engineers, developers, regulators, and communities from the outset. Feasibility studies must assess not only structural integrity and compliance but also long-term sustainability, financial viability, and cultural value.

Key strategies include:

• Structural and spatial integrity: Assessing the feasibility of retaining existing structures and identifying areas for strengthening to accommodate new spatial configurations and services.
• Human-centric design: Enhancing indoor environmental quality, accessibility, and well-being through biophilic elements and inclusive design.
• Financial and regulatory alignment: Leveraging green finance, incentives, and cost-benefit analyses to ensure commercial viability and compliance.
• Urban integration: Ensuring connectivity to transport and amenities, and contributing to the circular economy by repurposing rather than rebuilding.

Case studies: innovation in action

137 Market Street

This project exemplifies the benefits of adaptive reuse. Ramboll, as the civil and structural consultant, added three new floors to a 14-storey 1970s commercial building without requiring new foundations. By applying load replacement methods and lightweight composite steel frames, the team retained 56% of the original structure and reduced the building’s total load by 5%. The result: an embodied carbon saving of 1,879,500 kgCO₂e—equivalent to the lifetime absorption of 1,880 trees.

Capella Singapore

At Capella, two conserved pre-war buildings were seamlessly integrated into a luxury resort. Instead of commonly used secant bored pile walls, a permanent soil nail system was used. This alternative solution reduced embodied carbon by approximately 685 tons CO₂e and preserved the site’s spatial and historical integrity.

Plaza Equatorial

This redevelopment project in Kuala Lumpur demonstrates how new builds can still embody the principles of adaptive reuse. With an Embodied Carbon Index (ECI) of 400 kgCO₂e/m²—60% lower than Singapore’s BCA benchmark—the project achieved GBI Gold certification through integrated passive and active design strategies, including efficient chiller systems and other sustainable innovations.

Paya Lebar Quarter (PLQ)

Ramboll was engaged as the water management consultant. As Singapore’s first private mixed-use development to receive ABC Waters Certification, PLQ replaced traditional detention tanks with rain gardens and drainage cells. This eliminated 1,081 tonnes of CO₂e and created more biodiverse, community-friendly, and thermally comfortable outdoor spaces.

Courage to reuse, vision to transform

Adaptive reuse is not without challenges—structural limitations, outdated materials, and regulatory hurdles can complicate projects. But the courage to challenge the status quo, supported by progressive policies and incentives, is essential.

As Dr. Hossein Rezai-Jorabi, Ramboll’s Global Design Director for Buildings, rightfully puts, "What we lack, at times, is the courage and the policies that are needed to save our buildings—and with it, the life on this planet.”

In Singapore, where the average building lifespan is 40–50 years, giving buildings a second life before demolition is not just a sustainable choice—it’s a moral imperative. Designing for longevity and adaptability is, by default, a decarbonisation strategy.