Hemp concrete: carbon-negative construction
The onset of heavy greenhouse gas (GHG) emissions from conventional construction practices has led to research on several plausible low-carbon dioxide footprint construction materials that are either carbon dioxide neutral or carbon dioxide negative. One such ‘green’ construction material is lime hemp concrete (LHC), hemp concrete or hempcrete, which are some of the many names of this novel construction material. Hemp concrete is essentially a composite made of lime and hemp shivs. This paper presents a literature review of the various studies carried out on hemp concrete to understand its properties, drawbacks and advantages in construction. The review dwells on discussion of hemp, use of lime as a binder material and the mechanical, thermal and hygric properties of LHC. The salient features of LHC with regard to mechanical, thermal and hygric properties and ecological impact are discussed in the paper. It is observed that further research on LHC is required to be able to establish mix design principles, improve the compressive and flexural strengths of LHC and its use as a load-bearing structural material for high-rise constructions and establish cradle-to-death GHG emissions, recyclability and reusability which seem to be promising propositions with hemp concrete.
