Carbon Sequestration Pathway for Building Enclosures

 Our construction practices directly impact the global GHG emissions, of which the US contributes  a third, and manufacturing and construction accounts for 11% [3]. Addressing climate change  requires a reduction in embodied carbon from construction materials. While reducing carbon  emissions is crucial, the Intergovernmental Panel on Climate Change (IPCC) emphasizes the  importance of simultaneously drawing down and storing carbon to keep global GHG emissions  below the 1.5°C mark [28].  

As our terrestrial opportunities for extraction decrease and the need to address climate change  becomes more critical, designing building envelopes with their carbon sequestration capacity in  mind is increasingly important. Envelope designs alone can directly and indirectly impact up to  60% of the carbon emissions associated with a building varying by project type [32].  Experimentation with bio-based construction materials such as Cross Laminated Timber (CLT),  hempcrete, bio-concretes, and mycelium composites, which sequester biogenic carbon through  photosynthesis, carbonation, or bio-mineralization, is ongoing. Additionally, advanced materials  like Building Integrated Photovoltaics (BIPV) offer alternatives to significantly reduce operational  carbon requirements. This research aims to study pre-designed bio-based, high-performance, and  conventional building assemblies for their potential to store carbon. The assemblies will meet an  R-30 for consistency and will be evaluated for their implication on a baseline residential building  model for climate zone 5A. The bio-based assemblies will be selected based on their material  properties like durability, scalability, thermal conductivity, fire resistance, and density. This study  aids practitioners and decision-makers with a better understanding of our envelope’s ability to  store carbon and highlights the need for more regulated policies for embodied carbon  benchmarking and EPDs in the market for bio-based products. Additionally, this research  encourages the use of Life cycle assessment tools like One Click LCA that quantify biogenic  Carbon.