GREEN GROWS HOUSES Explorations into reducing Built Environment Embodied Carbon Emissions by promoting strawbale as a construction material
Abstract Global warming is a pressing issue that requires immediate attention. Consequently, Architects have an immense responsibility to promote renewable bio-based materials with innovative construction technologies in the construction industry to reduce operational and embodied carbon emissions. This research, focusing on embodied carbon emissions of materials, aims to identify strategies for reducing these emissions in the construction sector by promoting strawbales as a building material. Unfortunately, despite its significant potential as a building material, strawbale remains underutilized in New Zealand. Additionally, there is a considerable knowledge gap regarding emission reduction strategies in the industry.
This thesis investigates how effective strawbales are as a construction material in reducing embodied carbon emissions in comparison to conventional materials. The method involved conducting a life cycle analysis of materials to comprehend the areas where embodied carbon emissions occur throughout their life cycle. This approach uses the BRANZ LCAQuick tool to calculate embodied carbon emissions and visualise them using bar graphs. Furthermore, construction details also have been developed along with strawbale material properties to find solutions to adapt strawbale as a material for the construction industry.
The results have clearly shown that strawbale has a significant potential to reduce embodied carbon emissions due to strawbale’s carbon sequestering capability as compared to conventional materials. However, there were many challenges of quantification due to limited data and assumptions. The BRANZ LCAQuick tool has limited data, making it challenging to quantify certain materials and products. However, the work shows that a combination of strawbale and timber constructions may be a good solution to reduce embodied carbon emissions. Additionally, this combination of materials has the potential to sequester carbon in the built environment over a long period. Yet, careful management of the carbon cycle of materials is essential, even though these are biobased materials.
This thesis concludes that to build a zero-carbon environment going forward, all building elements and materials of the design should be considered through responsible management of the carbon cycle of materials. Simply changing one building element into a bio-based material may not be enough to achieve carbon budget levels in New Zealand. Also, it is essential to implement innovative construction techniques to promote biobased materials. Additionally, a well-developed standard method to calculate embodied carbon emissions for New Zealand is essential.
