Life Cycle Assessment of a Wall Made of Prefabricated Hempcrete Blocks

Abstract:

Hempcrete is a natural building material obtained mixing hemp shives (i.e., the woody core of the hemp plant) with a lime-based binder and water. Hempcrete as construction material is gaining increasing interest as the EU aims to achieve net zero emissions by 2050. This material has, in fact, the ability to uptake carbon dioxide from air (i.e., via carbonation) and to store carbon for long time. The goal of the present work is to deeper analyze the environmental profile of hempcrete, in order to assess its potentials in reducing emissions of construction sector. Specifically, Life Cycle Assessment (LCA) of a non-load-bearing wall made of hempcrete blocks is carried on. The analysis encompasses the whole life cycle from the extraction of raw materials to the end of the service life. The analyzed blocks are produced by an Italian company. Only aerial lime is used as binder, microorganisms are added to the blocks to accelerate carbonation. The impact on climate change is assessed through the GWP 100 method proposed by IPCC. Preliminary results reveal a nearly neutral carbon budget.

• Periodical: Construction Technologies and Architecture (Volume 1)
• Pages: 436-442
• DOI: https://doi.org/10.4028/www.scientific.net/CTA.1.436
• Online since: January 2022
• Authors: Valeria Arosio*, Chiara Moletti, Giovanni Dotelli
• Keywords: Carbonation, CO₂ Uptake, Hemp, Hempcrete, Life Cycle Assessment

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