What is Carbon Sequestration?
Carbon sequestration refers to the process of capturing and storing atmospheric carbon dioxide (CO₂) to reduce greenhouse gas levels. In nature, forests, soils, and oceans act as carbon sinks. In building construction, carbon sequestration involves materials and techniques that lock in CO₂, preventing it from contributing to climate change.
How Carbon Sequestration Enhances Sustainability
Incorporating carbon sequestration strategies into buildings reduces the carbon footprint of construction and operation. This approach aligns with sustainability goals by mitigating emissions and promoting circular economy principles.
Applications in Building Design and Construction
- Biogenic Materials:
- Wood: Timber products store carbon absorbed during tree growth. Mass timber, such as cross-laminated timber (CLT), is increasingly popular for carbon-sequestering structures.
- Hempcrete: Made from hemp fibers and lime, hempcrete stores CO₂ and provides insulation and durability.
- Bamboo: Rapid growth and carbon storage capacity make bamboo an excellent sustainable option.
- Carbon-Storing Concrete:
- CarbonCure: This technology injects captured CO₂ into concrete during production, reducing embodied carbon.
- Biochar-Enhanced Concrete: Biochar, a form of charcoal, traps CO₂ and improves concrete’s thermal properties.
- Green Roofs and Living Walls: Vegetative systems absorb CO₂, improve insulation, and enhance air quality in urban environments.
- Recycled Materials: Using reclaimed materials prevents additional emissions and reduces waste, supporting sustainable construction goals.
Strategies to Include Carbon Sequestration in Building Design
- Prioritize materials with high carbon-storing potential during design phases.
- Utilize life cycle assessment (LCA) tools to evaluate embodied carbon in materials and construction processes.
- Incorporate modular and reversible design principles to extend material lifespans and reduce demolition waste.
- Work with suppliers who prioritize carbon-sequestering materials and practices.
Challenges and Opportunities
While materials like CLT and carbon-storing concrete present opportunities, widespread adoption faces challenges like cost, limited manufacturing, and regional availability. Research and development continue to improve scalability and affordability. Additionally, if buildings are ultimately demolished and disposed of in landfills, then sequestration of biogenic materials is essentially lost.
Conclusion
Carbon sequestration transforms buildings from carbon emitters into carbon sinks, fostering sustainability. Adopting these strategies supports global climate goals and reduces long-term environmental impacts. By prioritizing carbon-sequestering materials, the construction industry can lead the way in combating climate change.
